My game has evolved since I first started playing. Some things have been for the better and some for the worse. One of the holes in my game used to be calling with junk (or speculative hands if you want to be charitable). Don't know why but there were all of these lowest 10% hands that I would play. Sometimes it was to defend blinds, other times it was because there were so many others already in the pot. Not only would I play these hands but I'd call raises with them also. I'm sure that the chart of the EV on those hands would go through the floor but of course I would get *just* enough carrots to keep me coming back for more even though the one pot that I would win comes nowhere close to covering the losses on the dozens of pots that I call/fold. Sure if the 92 hits in a big way then you'll probably win the pot but any flop where 92 is hitting big is not as likely bring as many second best hands as flops with Broadway cards. Some other players can get away with playing junk but since I don't bluff it is basically impossible for me to win with second best hands which you are going to have a ton more of when you come in with crap holdings.
I have cut down a bunch on my any two cards play but I'll still play baby suited cards, 69, J3 and other goofy hands. Can't explain it but for whatever reason, I still like splashing around with a hand like 64 or 72os; however, the difference is that I no longer pay way too much for them. With the limp/fold at my disposal I can still scratch that itch to play crappy hands but get away from them when it costs me too much. One BB to play 3d5d? Sure! But if someone raises I can now lay it down and wait for a better spot.
That leak in my game has now been throttled down to a manageable trickle and I'm fine with that. A junker hand can now only cost me an extra BB every once in a while thanks to the limp/fold maneuver.