I did get the distinct sense that we were not supposed to masturbate at all. No one ever said this explicitly. Instead, I frequently heard staff and oldtimers speak negatively and harshly about "fantasizing about chicks" or "getting into your head about chicks". I suppose it's technically possible to masturbate without fantasizing but I never had much luck with that. I recall one guy even feeling guilty about having a wet dream and he asked a staff member what he should do. "Enjoy it." was the reply. The reason given was that you have no control over such things. But purposeful, conscious masturbation was a different matter. Every guy I talked to got the same impression as I...it was a no no.
I went 'without' for my first couple of months at the Seed and then decided to heck with it. This resulted in feelings of guilt and I'd never experienced even the slightest guilt feelings about masturbating before the seed. My moral inventories are full of lines berating myself for fantasizing about chicks. It created a war within myself & shame where there was none before.
My guess is this puritanical aspect of the Seed came from Art's (& other staff members) catholic background. Whatever the source, it was a twisted aspect of Seed ideology.