It's time for "Famous-for-SF Chef Swap," everybody. Ready? With the departure of low-rent Eric Ripert impersonator Laurent Gras from the Fifth Floor this week, the foodie-retard scene is all abuzz with speculation on when he chose to go, where he'll end up, and how his replacement, Melissa Perello, will fill the gap. We won't add to the speculation as to whether Msr. Gras is headed back to NYC, but we can offer some counterspin to the party line on Perello.Ed. Note: With a gleeful cackle, we introduce Doyle, our intrepid restaurant dish hound. There are few businesses as vain, incestuous and duplicitous as high-end dining, and we heirloom-tomato and habañero-pepper relish the chance to pass the toque, clog and check pants gossip along to our readers. Got a tip on bad tippers? Email us and your confidentiality is assured.