Aboslutely true alan, but scent never hurts either.
Andy, try a few floating beads to the hook, just above it, and give it plenty of bait. Add some squid to it or try mackerel strip, both of which are stronger baits and can be whipped on with bait elastic to provide added crab busting ability. Try using a three hook flatter rig and extend the topmost and middle snood beyond your normal distance, say to 12 inches long, especially on an ebbing tide, less so a flooding tide.
The beads let the bait bob around in the current and cause the crabs more problems but a flatfish will happily swim up to take a decent bait. Flounder can be very finicky feeders but around this time of year the pickings are very slim and with a decent bout of hunger, they get less selective and will happily tuck into anything edible including chicken fillet!
FWIW...