No, class is not contain-ability. At least not initially. I guess after a while some people with "rules-itis" changed about everything in SCP. That's why most of the original people left. This is what happens when you open up your creation to everyone and anyone. SCP no longer has much of anything to do with the original intent and feel. It's turned into standard bad fan fiction, and children arguing over it. I mean, EVERYONE has their own view on what SCP is, right? So all stories are good, right? That's why they had to tighten the rules, but for the worse. I remember in early days of D&D, everyone's idea for a new monster was a 20th level monstrosity that could kill Orcis. Just what happens when the "masses" don't get IT.