You can certainly string higher but it'll just reduce the playing life of your racquet even more and put it at risk of cracking.
I frankly don't see the benefit of stringing over 60lbs. Personally I would be a bit worried everytime I take a full blooded swing on a fast incoming ball.
If you need that much control, switch to a more flexible lower powered racquet.
Last edited by Jay_The_Nomad; 10-05-2012 at 11:20 PM.