That line about heat pumps being a modular toolkit?
Well, any decent heat pump now can operate at several capacities. If your heating load requires a 4-ton heat pump but you only need 2-rons of cooling, then you could *absolutely* use a 4-ton heat pump so long as it's configured to run as a 2-tonner in the summer.
This all gets back to weedsy details and not keeping up with the pace of innovation. Lots of well-intentioned misunderstandings in the industry still hanging on.