I've obviously been thinking a lot about how and when to attack raisers of late, as I do think that taking down one's fair share of raised pots is an enormously important aspect of poker success. Up to now, I've really been looking more at the looseness/tightness of the raiser, but I think that's really less important than the strong/weak distinction.
A strong raiser, whether loose or tight, is just one who's going to follow up the vast majority of the time with a serious continuation bet and is in general likely to put a lot of money into the pot before laying down. Whether or not this raiser is loose or tight, you want to have a solid hand before getting involved with this player. I'm really inclined to call raises against this player only with PP or AK. For reasons noted in a post I made under "attacking tight raisers," I think there are sometimes advantages to being out of position against this player (some flops may allow you some potential for taking down the pot uncontested with a little pair or such). Sets certainly aren't going to get paid huge every time, but the willingness of this player to put quite a bit of money out there after his raise should be quite sufficient to make it profitable to just wait around until they hit most of the time.
A weak raiser is very different. I'm including in this category (again regardless of how loose or tight) those inclined to slowplay aces, making lots of weak continuation bets, and, worst of all, those checking flops they don't like. The difference here is very simply that the "weak raiser," as I'm calling it, is passive, for whatever reasons, in playing the flop.
I'm not sure exactly HOW yet, but I think this is the raiser that one needs to think about attacking a lot more often. Regardless of what they have, they make the attack cheap. Against this type of raiser, I think it is definitely an advantage to have position, because they're going to be a lot more inclined to tip their hand than the strong raiser. It just may take a while to figure out exactly what they're doing with these varied bet sizes, and they may mix it up, too.
I'll just give an example from a very easy version of this raiser (I'm pretty sure this is the raising strategy of a particular player in our game): Raise 99-AA, AQ/AK. Check flops with overcards or missed AQ/AK.
Well, it's pretty obvious that this player is going to miss an enormous number of flops. 99-JJ are all going to have overcards most of the time. AK and AQ both miss 2/3 of the time. So, we're going to see a lot of checks.
In position, I think you can play a very wide variety of hands against this player (particularly if you only have to deal with one additional player calling the raise with you). I'd say AJ-AK, KQ, all suited connectors, and all PP is a pretty decent hand selection for calling this raise. In position, my intention would be to bet to a check here pretty much every single time on those hands.
I'm going to have to get some more data on the less obvious versions of these weak raisers, who are also much more common than the strong ones. I'm sure they have some major vulnerabilities, but I haven't quite figured out where they are or how exactly to attack them. I do think sets (or AK, with some qualifications) are the best way to attack strong raisers (and that does mean that I don't have any problem laying down suited connectors there).