One of the most useful plays at the low and mid stakes is making the odd well timed lead into a pre flop raiser. Weak players - particularly weak loose players - often really struggle to deal with players leading into them after they have raised pre flop. Weak players will nearly always call or raise with extremely marginal hands, making it an ideal situation to build a big pot when you do hit a hand.
Feeling unable to just give up the hand, they lower their calling and raising standards and give action in spots where really they need to be able to just back down.
Their reasoning is pretty straight forward, and based on the fact that they have shown the pre flop aggression, probably intended to fire a continuation bet at nearly any board, and have difficulty reconciling this with a player now showing them flop strength. Feeling unable to just give up the hand, they lower their calling and raising standards and give action in spots where really they need to be able to just back down.
This is a particularly useful tactic when playing sets on the flop. As sets are strong hands, but ones that are vulnerable to draws, it is important to try and give your opponent the wrong price when you hit one. Imagine you defend your big blind from a button raiser with 5h5c and see a flop of 3h5c10h. Here is a great spot to lead into your opponent and hope they call or raise. As they are in position and have shown the pre flop initiative, they may well reason that you can be forced off a weak ten or other pocket pair, and either try to raise you off the hand or call intending to take it away from you on later streets - all good news for you sitting on a monster.
There is one key area of this strategy that is problematic though. Against players who you sit with day in, day out, you need to be able to bluff occasionally in spots like this to balance your actions. As this play typically generates action for you, it can be quite and expensive bluffing here if mis timed, although against regulars it is essential to balance your range of hands, and ensure future action when you lead out.
Taking the momentum away from pre flop raisers can be one of the most profitable tactics in poker. The desire to stay on top of the hand seems to make many players vastly over play quite weak hands, all of which can very quickly add up to a lot of extra profit.