My mother is also obsessed with warm plates. Except they're not warm, they're scalding hot and involve much juggling to handle, burned hands and 'mind the plate' warnings. It's all such a faff.
I make a bit of an effort for Christmas dinner but that's about it. Having grown up with hot plates and not doing it now, I can't see it makes that much difference to ordinary everyday meals (i.e. Chips cooked at warp factor 220 
)