So I'm not 100% sure, but I think that the first implementation of IsSuperMajority() for MASF was done for BIP-30 (0.7) and everything before that wasn't really decentrally "activated". I think that this is when Gavin first proposed code for it, but maybe I've missed something. This was the "novel" mechanism when I started looking deeper into Bitcoin code.
I think that BIPs 30, 66 and 65 were activated using this, then from 112/113 (CSV) onward, versionbits were the primary activation indicator instead of hard version numbers.
IsSuperMajority()for MASF was done for BIP-30 (0.7) and everything before that wasn't really decentrally "activated". I think that this is when Gavin first proposed code for it, but maybe I've missed something. This was the "novel" mechanism when I started looking deeper into Bitcoin code.