I only started running this game less than a week ago but I'm pretty sure a sub 6 is possible. My 6:15 has really good RNG, but there were a few notable time losses, like when I messed up dialogue on the tribe, when I accidentally took a few steps in the saloon after giving the pianist the score, not clicking the clocktower twice, getting hit by a bomb in the final fight, and probably a few more. I think that some more optimized mouse placement and less messups can lead to a sub 6, although that goal seems far away from now.