(Side note to previous message: adding points [that you receive by leveling up] to your stats and skills will simply add onto the glitched stats, so it's safe to do this if you're glitching.)
A note about Sam's glitch: if you reset your attribute points, it also resets your 'cheated' stats back to what they should be. So if you use this glitch, DON'T RE-SPEC or you'll lose the added stats.