the seconds

You can set your bid for 2 seconds if you want, but you greatly increase the risk that eBay will not be able to accept your bid -- whether it's placed through AS or manually -- because eBay's servers are too busy. This has nothing to do with AS, which will place, or try to place, your bid at the time you specify. However, it has everything to do with why the guidelines recommend 5 seconds, minimum.

I've been using AS for more than a year now and getting along splendidly with an 8-second timeset. The times I've been outbid have been when my maximum bid wasn't enough.

I have been using the standard 5 second snip time and find that my bid is being posted on eBay at 9 seconds prior to the end of the auction. I suspect about the same time delta would apply to any snip time you set. Seems that either AS is not placing the bids when they say they will, or they have not bothered to sync their clock with eBay's. This could be a real problem if you don't know about it.