This is a question that I dont think can be given a general answer. So much depends on what your reads on the other players are, and your own image. The other players stacks etc etc. Here´s my personal strategies to play tricky hands like JJ, deep in tournaments.
If I have a decent stack, well above average. I dont play them unless I´m first into the pot. (Except when in SB/BB and button is the only one in the pot, then I reraise any raises but fold to a raise that committs either mine, or Enemy´s stack) I fold them UTG, I raise them late, and in mid pos it´s more the table than the cards that makes my deciscions for me really. On a supertight and weak table I raise but never too much to committ me if a tight player akes up with a reraise. I´m always prepared to lay them down on a flop thats dangerous or if I get multiple callers.
If it´s close to the bubble, I attack midstackers, but never shorties or major chippies.
If I´m shortstacked, I push, regardless of position. I don´t play to pay the coffee, I play to win and folding JJ shortstacked to survive the bubble is to weak for me.
Like any other higher pocket pair, JJ is very strong preflop unless reraised a lot, but it weakens once the flop comes with a pair or overcards. If you have a lot of chips, you dont want to play huge pots with them, but they are great to bully midstacks and (very) small stacks with, if they tend to look like they prefer to last over the bubble. They are also good enough to push if you are low, but main thing for me, is to avoid all in preflop/playing big pots against a stack that can hurt you seriously.
Needless to say, this goes for any hand, but JJ is trickier than most cos they do look damn good... at first.
My point of view, far from pro, but at least I make money on the game so maybe it´s worth something.
