[Ztcgtqvb]

I dunno. I've found cross training with other arts has helped my primary(s) beyond imagination. My first iaido seminar I went to helped my kendo immearsurably and a three hour workshop with an aikido guy has helped my zanshin and seme beyond all recognition of what it was. That said, my iai teacher wont teach me iai until my kendo basics are good enough so that I don't start getting confused.

I guess it depends on why your doing the art(s) and what you want to get out of them. Years ago I would have said focus on one but life's too short and there's too much good stuff to do. There's enough hours in the week for multiple trainings