WP34s Differential Time and shift

[MarkHaysHarris777]

My two Timex watches (Ironman Shock) are handy because their time(s) shift is opposite -- one is half second fast per day, the other half second slow per day. The difference between them tells me when they were synchronized, and the coordinated UTC, for my zone, is then half way between. A third timepiece (like the WP34s with crystal) can then be set accurately +/- second from the other two as absolute reference based on their differential times (or alternately, the WP34s once determined may be used as one of the differential time markers.

I am noticing that the time shift for my WP34s is almost precisely 1 sec fast per day; half minute fast per month (on average). A program can be written which based on the date and 34s time, along with the difference time in a second time piece (input data) could then reset the 34s for correct present time eliminating the shift mostly.

I am wondering if I can narrow the shift a bit on the 34s short of replacing the crystal... how the two caps affect the timing... and whether it would be easy to have the firmware (configurable) be able to adjust for the shift ??

TIA

cheers
marcus