Yesterday, I was in the park, training aikido weapons with friends from several different aikido clubs. There was no dojo. We were in shoes and on hard ground, so there was no seiza. There was no kamiza with a picture of O Sensei to bow to or raise our weapons to. We did not wear gis or hakamas. Were we still training aikido, or had we invented something else?
My personal take on it, honestly, is that that was an extracurricular special study session, where you practiced some forms that will help you do them better when you are in the dojo, where, being aiki weapons, they are themselves a kind of sidebar study of Aikido.
What if you lost your mat space and all you could do was get together in the park and practice weapons in street clothes? How long before you decided it was pointless?