I ran a Pathfinder game last night and, as I'm not 100% up to speed with the rules, I asked the more knowledgable players to help me out. Jason, a long time gaming collaborator and close friend, helped me out with some rules interpretations and was a great help during combat. Did he stack the odds in his favour? I don't think so. A fight between five 1st-level PCs and a badly wounded troll went quickly, smoothly and was a lot of fun for all of us.
Did I mind Jason helping me out like this, co-GMing the game? As far as rules are concerned, not at all. I needed the help and with everyone else knowing a lot about the game it was handy I had someone on hand to talk about the rules as well as page-flip as I dealt with other players. I'd have drawn the line at actual rulings but there was none of that, and the few rolls he asked to make didn't unbalance the game at all.
All in all it was a positive experience. I trust him to be right and I hope he trusts me to unfold a good adventure, and having some of the pressure taken off my shoulders was a massive relief. I'm looking forward to next week, now, as it's been a while since I ran a game with a complicated system in which I didn't need to stall the game as I made rulings from an encyclopedic rulebook. It honestly felt like I was running a rules-lite game with a rules-heavy system.