Leading into the preflop raiser is a standard part of my game now. Why limit it to just sets? I lead with all kinds of hands on the flop: sets, 2-pair, straight, flush, big draws, weak overpairs, and of course air on occasion. If villian is a c-betting machine, then leading is probably not your best choice.

Leading is a great way to disguise the strength of your hand if you do have a monster and also a great way to get the money in (with 100BB stacks) with a big draw and have a ton of fold equity at the same time. The line I like with a big draw is called bet/3-bet (via 2+2) where you lead for around 3/4 - full pot, get raised by a probable TPTK/overpair, and then you shove. Monster fold equity plus it makes it very tough for opponents to call 100BB's with just a pair, and even if you are called you are nearly a coinflip to win. Lately I've been using this line with flopped monsters and getting called routinely.

Also, at higher limits where players are more aware, it would be very commonplace for someone to just call a flop lead with a hand like TPTK and then check behind on the turn since they know that a flop lead could potentially mean a big hand and they are trying to reach showdown cheaply. So what am I saying? I think JohnnyFish's line is good against players that probably are too passive to bet big with TPTK/overpairs fearing sets, but too stubborn to lay them down. So once you identify these players start leading your draws, so you can get a free card.