If you want to short overpriced options safely you have to buy way OTM "garbage" options for insurance against a 87/flash crash scenario ex: if you think the AAPL 480 put is overpriced, you can short that but buy the 400 or something like that. That way you know the most you can lose This is the approach endorsed by long-term options veterans like atticus who survived lots of these big events
Better hedge is to be small. You can't claim to sell insurance and then not be able to payout when the storm hits.
So a spread basically? Only problem is, spreads allow you to overleverage. They have less theta, require more risk for the same return %, and if it drops below your long strike you are screwed. A short spread is like a long stock at X with stoploss Y. A naked short put is just long stock at Y. The naked short put has less risk. As newwurldmn said, it's better to just stay small and relax. It's even possible to (shock) limit the risk w/ a normal stoploss like you would a stock position. For some reason people assume that when you're short option you can't buy it back and realize a loss at a % tolerance draw down. If someone buys a protective put to sleep better at night and he's overpaying for this put, then the seller of that put is expected value positive.
Perhaps also try this thread: best ways to go long/short volatility... http://www.elitetrader.com/vb/showthread.php?s=&threadid=248602&perpage=40&pagenumber=2