It took three more cases after he locked Neal Caffrey away before Peter realised that he was using the man as a measurement for other criminals.

Neal had been his biggest case, the one which firmly cemented him as the darling of the White Collar Unit in New York's FBI office. But after he arrested him Peter found himself comparing all the others to him.
'Neal wouldn't have forgotten to have a second back exit' was one thought as he held a man's head as he put him in the back of a squad car. Or 'Neal's papers were of a much higher quality' when looking at some fake bonds.

Then came the day of the Dutchman, three years and nine months after he put him away - the day when Neal walked out the front door of the supermax. he was telling the truth when he said the Dutchman may be as good, may be. But as always, not good enough, as many of the criminals he'd put away had figured out. Neal had shown just how good he could be.

Peter was just glad to have the yard stick he measured by close enough to take accurate measurements.