On the ZX forum, one of the posts said his chicken strips were "father of two young kids with a mortgage" wide, 1". I thought that was a great answer, because it shows his unwillingness to take an unacceptable risk of crashing.
How far you can successfully lean your bike over is a combination of three main things: tires, skill and risk.
You can increase your skill and buy better tires, but there will always be risk. If you lean your bike all the way over, you increase your risk of losing traction and lowsiding or highsiding if:
-you hit a small patch of dirt, oil or uneven pavement.
-the turn gets tighter (reducing radius - you will ride off the road).
I believe that chicken strips are a measure of your skill combined with your tolerance for the risk of crashing.
Having said all that, mine are 1/2" on the FZ6R and 1/4" on the ZX14.
I find the OEM FZ6R tires greasy in the corners, not confidence inspiring.