No, it is not flawed, read my first post. You can protect against shorts, but you need an intelligent battery balancer, or two voltage regulators would work as you mentioned, same basic idea. I never said a "Y" would protect from shorts, I belive you read something into my post that wasn't there. I was answering two ideas, I probably should have made two paragraphs and not run them together. My premis is that full redundancy all the way up to just before you get to the RX seems, well, not redundant. You said shorts didn't happen enough to worry about... I'll give you they are rare. If all you are really worried about opens in the switches, then I suppose a single "Y" to the RX would be fine, but it seems pointless to me becase you only made part of the system redundant.