Y harness for dual 2s lipos, safe?

[mahazael]

Is it ok to make a Y harness for 2 2s lipos (effective 4s?) Both batteries going into a single battery leads?

I will be using a quark monster pro but will make a Y harness to connect both batteries into the Quark single battery lead. Reason is, I run an emaxx 3905 and want to keep the batts on the sides and I have mounted my 1515 center line (single motor mount).

Good idea? Dumb?