We haven’t really been using isPhysical, because it’s not always possible to tell in the DTH. Z-Wave Switch uses a kind of hackish trick, it send a different kind of get when polling vs when actuating so it can tell if the incoming report was from a poll (whether dth or hub-based) which indicates a physical event. Remember that very few Z-Wave switches actually send us a report when they are toggled – we have to rely on polling and watching for node info broadcasts.
The physical event tracking was taken out of Dimmer Switch in this commit, accidentally I assume: https://github.com/SmartThingsCommunity/SmartThingsPublic/commit/9d016839
Personally I think we should drop it all together because it’s not consistent.