PC-less WSPR the XORgan and Timing

Most QRPp'ers will know of my method of timing in my PC-less WSPR Keyers. (look at that I am being PC and saying PC-less).
I had query the other day regarding the XORgan 'have I considered adding GPS timing as a facility on my system'.
Well it has the facility, however my concept back in March 2008 was to abolish such things. Here were my thoughts:-
I smile at the huge power used by PC generated WSPR and a Transceiver to produce the few mW needed to span the globe. Why in a PC-less system then, add GPS timing to put the current consumption back up? Not to mention the complexity, QRPp'ers like to KISS.
Just because a Windows computer is a lousy time keeper why should we consider it impossible to keep time as accurate as the needs of WSPR. Heavens I had a fully mechanical wrist watch 40 odd years ago which kept perfectly adequate time for the purpose. Does the Quartz watch on your wrist deviate more than a second in a Month? We QRPp'ers have got to be able to do better than resorting to GPS, MSF etc.

My KISS approach:-
Use a good quality Quartz Crystal for the PIC timing oscillator, pre age the Xtal. Write the WSPR PIC code timing for that Crystal. Sounds easy, you will have to work out the figures needed and a method of checking the accuracy of the result. Of course I cant supply the code to do it for your Crystal. I suggest that if you don't already have a PIC WSPR generator you start with the SM6LKM code which is on the web.

Does it work:-
Well I have had an MEPT QRSS with WSPR ident on 10.140073MHz running 24/7 since early April 2008 I try to visit it every so often to push the manual re-set, other than that it is Quartz timed.