Re: latency, a story... The landlords for a house I lived in once had installed some German European-style electric rads which contained a pile of ceramic bricks. They were far more efficient than regular electric baseboards for obvious reasons. The problem was they just weren't up to the job of handling a Canadian winter. Not because they couldn't keep the house warm enough but because we are prone to extreme temperature swings. From +16C to -20C in 24H is entirely conceivable and happened one winter while we were there. We froze for hours while waiting for the bricks to heat.

The conclusion I came to is that heating systems like this with huge buffering capacity make sense for western Europe where weather systems are relatively stable. But continental climates swing too quickly.