The aggressive maniac can change the table in a few different ways. Some players like to follow the aggressor up with a re-raise for any hand they are comfortable playing against a raise where they don’t respect the raiser. These raises are predictable and easy enough to interpret. A player with a mediocre hand like 99, TT, JJ, AJ or AQ will raise when they think they can isolate the idiot. If you aren’t on the button or cut off be careful – don’t make the same mistake. With JJ a raise may be correct, but with the other hands you are too likely to get into marginal situations and lose more bets than you win in the long run (especially if he can let go of a missed hand). Worse yet if someone calls behind you a hand like 99 isn’t likely to win at all, and if they raise you’re in a very awkward position for the rest of the hand.
Remember that all you have here is less information, lower drawing odds, and a player that will make you pay to complete a hand. A raise is a raise if you’re holding a marginal hand (middle pairs, suited connectors, or weak top 40 high cards). Now remember if you’re on the cut off or the button and can play significantly better than your opponent and you can get a lot of information off raising the initial bettor then you may be better suited to play these situations. On an opponent specific standard I play marginal hands against a raise on the cutoff or button, but it’s because my opponents are willing to let me off cheap either by folding to aggressive betting on the flop or they are weak later in the hand.