It is an interesting issue, but wouldn't it be the opposite? If we don't count cumulative accounts, we could each get a vote for every 5000 sp we have by splitting it to multiple accounts?
I don't claim to know the answer, but @josephsavage's claim was that he could (theoretically) instead join each sbi account over 5k as a member, thus having more votes (35k sp = 7 accounts/votes).
maybe it could be something like this:
1.) account has to have 5,000 SP permanently
2.) one account = one vote
3.) with multiple accounts over 5,000 SP only one account is eligible to vote
--> one vote per dolphin
5000 SPS or greater makes a Dolphin account. Anything less and they will be asking for picture IDs next.