The trim
The back-gauge does not guess. It sits where the peak actually is.
A trim that "looks about right" is a ruined book. An apex that "looks tall" is a ruined hole in mist.
Soren zeros the gauge against a steel stop every open day. If the stop drifted, the bindery stays shut. Remaining peak is written in yards of hang, not in feelings. Willamette mist subtracts. Wallace wind subtracts more. A dry stall adds a lie.
Players who want one apex for every weather are asking the stitcher to ignore the trim. The card does not ignore weather.