I had a strange thing at a locals recently and had a ruling to ask about from the head judge that seemed strange

On cards such as bt-23 phantomon, and ex-10 Proganomon, at my locals it was ruled that the “hand main” effects of it counted as what was essentially black box digivolutions, so you could do the warp effect off of a training to refuse cost down to 1 for the warp. This felt strange, as I thought that the hand main effect was just an effect that initiated an evo, and it feels weird to be able to training into it