Anything that's both simple and mechanical is gonna have problems attracting investment. The guys you're talking to are gonna have problems justifying giving you 2/20 for buying a fund and selling options.
Or should. I've met a lot of investors who didn't ask the right questions.
Regarding the Sharpe, if they know what they're doing they're not just using the textbook version either. There's a paper by Andrew Lo about it, well worth a read, not terribly complex math.