I believe it's not a 'by-pass', but unity gain.
At 94, if you input 2V, you get 2V at the output. At 99, you will get more than 2V (no idea how much more).
Ideally, this holds true to every voltage, so an input of 0.4V would also yield 0.4V at 94, that would mean it's perfectly linear and, therefore, as much a by-pass as possible.
So, bottom line, these are not by-passes, they are just the value where the input matches the output. So, for a perfectly linear PRE with a 2x gain, that value would be at half the travel, or 50 in this case. I don't see why you would think that maximum should be unity gain?