Well, it's pretty risky to go below 5 seconds ... I blew away a competitor today using 4 seconds, but that was pushing it, and I knew it. However, it was extremely satisfying!
I shouldn't ;-) ... but I'll share this:
When in a reserve price auction, and when there are probably some people laying low, waiting for someone else to "fish" for the reserve price, do this --
Do lots of annoying, small increments ... work slowly up to the reserve price, provided it's in a price range that's acceptable to you. Do this no less than two days away from the auction end. After manually placing ever higher "maximum amounts," get to the reserve price and then DISAPPEAR. WAIT for others to come sniffing, maybe someone else will place a bid just above you, maybe they'll just wait in the weeds.
Chances are, they'll think you've topped out, that you're pretty sure you're the only one interested, that you're oblivious to the last minute sniffer. Then place a maximum price/snipe at AS for a price that's a comfortable cushion above your last posted bid, above all but what the most bloodthirsty bidders might bid, people who HAVE to have that item. Make sure your very MAXIMUM bid is still comfortable to you.
Set the lead time at 5 or under ... 4 is pushing it, maybe 5 is still best for safety. I used 4 seconds today and blew someone away who was sniffing around, testing the waters with a timid, "slight elevation bid" during the last two minutes of an important auction for me.
It was SO-O-O satisfying to blow right past using AS, and snatch the auction ... hehehe.