Lehman and etc. were killed by concentrated short selling for the explicit purpose of "trading for effect." There are already rules against that; enforcement them.
I'm for uptick rules . . . and would suggest an order block size limit on short orders (say, short order size can be no more than 10% of the previous 5 minute's aggregate volume), so that a 0.05 uptick doesn't allow a sudden million-share short order wiping out all outstanding bids. Currently a huge order like that would get priority execution under exchange rules over all other sell orders that might turn the tick down and lock out shorts.
All the energy wasted on attacking "naked shorting" however IMHO is a diversion from the real issue: lack of enforcement against "trading for effect." "Pre-borrowing" is nearly meaningless: obviously the lender account of the shares can not be forbidden from selling the same shares in the following three days between execution and settlement. So the borrowing for execution and borrowing for settlement are by necessity separate events. On settlement day, available shares will be assigned to large outstanding blocks before small blocks, benefitting the wall street institutional traders, and leave the small traders "naked" and subject to forced buy-in! That means the average small traders would then have to buy put options if they want to bet against stocks, driving up option premium, once again benefitting institutional traders.
As we can see, at the lawmaker and their staff/lobbyist level, this attack on "naked shorting" is yet another attempt at using government coercion to benefit insiders at the expense of the rest of the population.
BTW, not all short sells or even naked short sells are betting against the market. One can short SDS (2x bear fund on SP500) instead of longing SSO when the market is expected to go up (and avoid ETF counterparty risks). It would not supprise me at all if most ETF's have far more shares floating around than there are assets in the funds, thanks to naked short selling. They'd be much less liquid if the fund had to buy or sell the underlying every time someone buy or sell the ETF shares.
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