Yes, can't guarantee that they are right as there is always the possibility that I have made a mistake.
The more I think about it, the more confusing it gets.
If one looks at the formula for thermal inertia, I=(kpc)^0.5 and expand it you get:

I=(W.m^-1.K^-1.kg.m^-3.J.kg^-1.K^-1)^0.5

Now if you want to maximise the possible energy transfer between two masses (say the air and the wall) then the Thermal Inertia for each element needs to be equal. If you want to store energy then they need to be unequal. This leads to a problem as you can change a number of parameters, you can change the mass, the surface area, the heat capacity or the volume, you can't easily change is the energy input (the Watts) as this is fixed either by the weather or the heater (so it is in effect constantly varying). So what you end up with is:

I[a] = I[m]
where [a] is the air and [m[ is the mass.

In longhand this would be:

(W.m[a]^-1.K[a]^-1.kg[a].m[a]^-3.J[a].kg[a]^-1.K[a]^-1)^0.5 = (W.m[m]^-1.K[m]^-1.kg[m].m[m]^-3.J[m].kg[m]^-1.K[m]^-1)^0.5

When in equilibrium this can be written like this:

1 = (W.m[a]^-1.K[a]^-1.kg[a].m[a]^-3.J[a].kg[a]^-1.K[a]^-1)^0.5 / (W.m[m]^-1.K[m]^-1.kg[m].m[m]^-3.J[m].kg[m]^-1.K[m]^-1)^0.5

If you want to store enough energy in the thermal mass to 'carry though the winter night', you will need the product of the [m] value to be a factor 3 larger(ish), so it can release enough energy over a longer period. But to release energy from the wall to the air, the wall must be at a higher temperature.
As you can't practically change your walls or what they are made of to suit the weather conditions you have to make a compromise.
Once you punch in some valid numbers you find out that you need very little thermal mass (Ed mentioned this on another thread, but in a different context) to give you the ideal ratio.

I think, but cannot prove without real data (data anyone), the reason that people in houses with a small air to mass ratio think that it is the mass that keeps the place warm is that they are underestimating the 'two foot thick stone wall' U-Value and the air leakages in the building. This is where a decent experiment is needed (I have one in mind).

Tony, got a link for that BRE research please.

Kedrick et al, 2012 draw a different conclusion, though were more concerned with a future climate.
"This modelling study has found that there is little difference in thermal comfort performance for future warmer weather
predictions between framed buildings and traditional masonry construction as currently practised in the UK"

I had another paper that basically said the same, was a Brazilian one though.

Found it:

Thermal Inertia and Natural Ventilation
by Goulart 2004

And Szokolay, 1985 thought that it only makes a difference when diurnal variation is above 10 K. A rare day in Reading, even rarer down here, though happens in Scotland's Eastern side.

Kedrick et al, 2012 is this, presumably:

https://radar.brookes.ac.uk/radar/items/8efc1c31-eada-e467-932e-e9213f76e39e/1/

But that, at least from the abstract, is only talking about overheating in summer. That's a tiny fraction of the year.

It also says: “Thermal mass can reduce overheating, primarily in the daytime, but it must be properly exploited by good design (good night ventilation, correct materials in the correct places).”

It does, however, go on to say: “It is suggested that it is possible to optimise lightweight housing to provide similar thermal comfort levels during occupied hours using ventilation and shading.”

Ie, thermal mass can help with overheating but there are other ways of doing so, too.

More importantly, it's talking about “a typical UK … house” so not likely with good insulation or airtightness.

Which we surely should all be trying to exploit

Solar gain can only be exploited when the sun shines! Where I live (East Kent) I reckon I can count the number of sunny winter days on the fingers of one hand. I might be a little pessimistic but not far off.

It's been clear blue sky today so far, but it's not common in the winter. Only one more week and it's spring.

Posted By: daserraA good reason to have plenty of thermal mass around them

I was thinking about just that earlier.
This makes them like one of my E7 storage heaters. High temp but relatively small amounts of thermal mass when compared to the rest of the building.
Just out of interest, next time you do a burn could you measure the temperature of the wall opposite the burner before and after the burn (hope it is not in a corridor ). Be interesting to see how much it goes up by.

I can and will although the wall is 7 m away and the stove only puts around 1-2kw into the room (and 10 into the water jacket). The wall behind is 500mm rammed earth so I'll also take a measurement of the other side of that in case it's useful.
I have a German neighbour here with a masonry stove in a poorly insulated building and he rates it highly.

Hers's showing where the WBS is in the scheme of things. The room it's in is a vented cavity wall, 20cm brick inside, 4cm cork, 6cm airgap, 20cm Ytong outer(0.34 U). The floor is uninsulated concrete (as yet) and the roof is 13mm pine topped with 90mm XPS then tiles(0.22 - 0.37 U depending on how I calculate it). The large glass area is double glazed (4-12-4) "thermal glass" with exterior aluminium thermal shutters (1.11 U)
The part behind the WBS is all 500mm original rammed earth construction, topped with 13mm pine and 30mm XPS then tiles.

That also surprised me although the flue is double lined with Rockwoll wrapped around it and the entire back and sides of the stove are water jacket so surface temps are low until the water temp gets up to nearer 70C. There's also some thermal bridges from the rammed earth, up to the tiles is uninsulated and the concrete "buttress" connects directly to the outside although it is extremely massive.
Nice to see those charts, thanks.

Posted By: funcrusherA point almost universally ignored is the critical factor of radiation.

I admit I do not fully understand the interaction between walls and people (though Ed has been very patient).
But if you have light weight walls, say plasterboard, would they not warm up quicker than a foot of stone. Then they could start radiating effectively?

From my work with solar pool heaters, if you shelter the non-glazed collectors from wind with a low wall around you get much better output.

We're well insulated, low mass, (the house, that is).

We've struggled in our heads the last few weeks, with the outside temp meaning that technically we don't really need to light the stove every day (indoor temp between 18.5-20C, slowly falling as chimney bricks cool down). However, we still feel a bit chilly if sitting doing nowt much and so have the stove on trickle fashion (I know it's naughty), especially when it's raining.

funcrusher's comments are very educational. Thanks,

ranging -1 to +10C, let's say average 7-8C. Incredibly mild for time of year. I reckon we would lose maybe 1.5 to 2C per day as exposed inner brickwork starts to cool if wood burner not on.

Tried degree days some time ago, but lost all data thanks to PC breakdown (not backed up, of course) and incompatibility with new kit, I reckon outside average temp of 13C or below, we need a fire on.

I doubt if 'wind chill', has a scientific definition, though perhaps 'wind chill factor' does. Many vernacular expressions eg 'heat' have later received a definition for scientific purposes.

'wind chill' is in my opinion simply a modern expression for forced cooling, which is a long-established if minor topic in physics but of great importance in metallurgy, as cooling rates are fundamental to properties of alloys inc steel. It is also a sub-set of forced cooling by fluids in general which encompasses heat exchangers and much more.

In any event, quite low air speeds have a dramatic effect on cooling rates of bodies inc buildings, as it disturbs the boundary layers of air, which act as a hidden insulator. Try wearing nothing but a string vest on (a) a calm day and (b) a breezy day. Cooling effects are magnified by surface roughness( the inverse of streamlining). So houses with quirky shapes with lots of protusions like dormers and bays suffer more. it would be interesting to know if ivy helps to insulate by stabilising the boundary layer.

Previous thread reference to shelter provided by walls needs qualifying. Solid obstacles produce dramatic turbulence , so unless the sheltering object is far smaller than the wall, the shelter effect is limited. Better to have eg belts of trees, where the wind is gradually brought to a halt. Even in the recent hurricane it came to pass that as I walked through an area of woodland, the under-storey was almost calm whereas high above the wind howled.

Note that our forebears (again!) got there first and most substantial houses were built with adjacent shelter belts of trees.

Crevices and moisture penetration can be a problem, but are an entirely different class from wind chill per se.