Chain drive systems have advantages and disadvantages. Are you really surprised about that? This has been discussed at some length in the chain drive thread. Overall opinions regarding chain drives seem favorable.

I think you (bdcain) are looking for problems where they don't exist. At least not significant ones. If it isn't jealousy, my next guess is you resent Optibike's high price. Guess what - it is overpriced. If that bother you, then don't buy one!

Specifically, chain suck happens on non-motorized bikes too. I don't see significant added risk here - sure the chain is pulled harder and could theoretically get stuck harder due to that, but wedged tight is wedged tight, whether from human power or a motor. FYI, the motor cuts out when stalled and won't likely tear the bike to pieces as you suggest.

As to the notion that anything should be considered foolproof, I think Douglas Adams said it best: "A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools."

By the way, you can't "piss on my parade." I'm loving my 800Li, and I'm not seeking acceptance here to validate that. You did get one thing right, though: having a machine shop is a very nice. I'm heading there now to make a better throttle.