Turned out it was a mistaken belief. Basically, thickness invariance in medieval glass had to do with the manufacturing process, and the viscosity of glass is n

Turned out it was a mistaken belief. Basically, thickness invariance in medieval glass had to do with the manufacturing process, and the viscosity of glass is not observable in a human timeline. https://ceramics.org/ceramic-tech-today/glass-viscosity-calculations-definitively-debunk-the-myth-of-observable-flow-in-medieval-windows https://ceramics.org/ceramic-tech-today/glass-viscosity-calc...