I think "spiritualism" is something that people shouldn't talk about at all.
Wow. That's pretty harsh.
I don't know much about God, the Universe and Everything and I'm certainly a fucking asshole, but I still find that my training in Aikido has been enriched by the discussions I've had with people about the spiritual, emotional, and daily practical relevance of Aikido to their daily lives.
In contrast, discussions of martial effectiveness have rarely done much for my Aikido. Places where my instructor has 'demonstrated' my openings have done a lot both for my martial effectiveness and for my Aikido, but usually no discussion was required.