"1t1v is like a 1a1v where every account has only 1 SP."

I don't even understand this analogy. 1t1v allows you to distribute your stake as witness votes as you will, but to only vote each SP once. If you have more than one witness you want to vote for, you can split your SP however you want. It's nothing like 1a1v, which only allows one account per user to vote, no matter if your other accounts have SP.