I just realized that I'm reacting to the following conversation.
A: "I think that xxx and hhh, jkjkj and lpoopik..."
B: "Could you repeat that again, please?"
The reaction I'm getting is due to the fact that repeat that is already symmantically suffient, so the amendment of again is only proper if a previous repetition's already taken place, like so.
A: "I think that xxx and hhh, jkjkj and lpoopik..."
B: "Could you repeat that?"
A: "I said that xxx and hhh, jkjkj and lpoopik..."
B: "Could you repeat that again, please?"
On one hand, I feel there's something to it according to the motivation above. On the other hand, by the same logic, one would be required to reduce repeat that, please to simply repeat, please, since it's implied that the repetition request refers to the statement made.
And since that seems a bitty nitty picky to me, I'm prone to question my reaction by reductio ad absurdum. Advice?