Replacing caps on a board without cleaning the board is almost completely and utterly pointless.
I recommend a full dishwasher cycle to remove all traces of conductive electrolytic after a cap replacement.
I agree with the above, provided you know what you're doing.
I suppose that with these sorts of things, CD lenses & capacitors both play roles in running a system (among many other components) and replacing/fixing these one by one can help. Thanks to forums like these, expected time devoted to trial-&-error can be minimized.