I know how its setup, and I stand by what I just said.
dunno why not just use 4pin molex to 3pin though and what not.
Im positive though it should not decrease pump performance and anything else.
Because think of it like this as I said with the 4pin molex, You can stack like 20 fans together with them, and still not see a difference, as you can keep connecting a 4pin to another 4 pin to another 4 pin to another 4pin ect.
The same concept for what you are trying to do so to say, you are just adding onto the connector to make it viable with 2 fans. per connector.