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Mercy...I'm home with the plague, probably should just be reading and not typing...

8 to 10 weeks! 

I had a similar problem with crazing on my first FP attempt last year (actually my first attempt at everything).  As opposed to Michael’s description of making one pass of overlapping strokes per bodying session, I was making multiple passes over the same area (would usually divide the back and front into 4 zones) until the muneca started to drag.  I would then add the couple of drops of olive oil and then would make even more passes over the same area unil the muneca again started to drag.  At that point I considered that particular bodying session finished for the area I was working on and would move on to the next quadrant.  I would guess that each square inch received 10 to 12 strokes during my typical sessions (not at one time but moving back and forth across the entire application zone).  I made sure the muneca was loaded properly and always watched for a proper vapor trail.  I also always spirited off between each bodying session as Michael recommends.  I probably ended up with 10 to 12 bodying sessions when I was finished.  The end product was a overall smooth glassy finish with occasional small defects consistent with a first attempt.

However, I developed some small areas of fairly significant crazing about half way through the process as has been described above.  I attributed it at the time to fluctuations in the humidity levels and temperature as a result of working in my basement shop in the middle of a Chicago winter.  I level sanded those areas a bit and then stiffed off the areas a couple of times to melt the shellac and flatten the remaining ridges in the crazed zone.  That seemed to work quite will and the level glossy finish returned.    

A year later, the smooth glassy finish I completed the process with has developed some very fine crazing in quite a few areas.  It’s almost invisible unless you inspect the surface at just the right angle.  Based on Michael’s application method above, I would guess my shellac applications were too thick in the bodying sessions and the finish slowly crazed as the shellac completely cured over the last year.

Michael, I assume I could go back now with some additional stiffing sessions with alcohol only and remelt the surface and eliminate the crazing?

I think Robbie O'brien hit it on the head...if it were the Shellac only, and it was bad...it would be a gummy mess not cracking. After you sand back to wood...I would use Naptha to "wash" the wood real well and then try usin some Z-poxy for a pore fill. If you did "michael's glass test" then you will know in a few days ( while letting the z-poxy cure) if the Shellac was bad. I have had bad Shellac, but it always wound up having a drying problem that resulted in a soft or gummy finish, never had a cracking problem.