Yes, the pawl spring can break on you at almost any time while on the road. A regular happening at the larger gatherings of Airheads is the one or sometimes two people with broken pawl springs. The transmission will not shift and will be stuck in what ever gear it was in when the spring broke. If in 3rd gear you might get to ride it home providing it's highways to your house. If it's in second gear you might get around the neighborhood. It it's stuck in 5th gear you might burn up the clutch getting home.
To fix is not an impossibility on the road. Need some time, the rear flange puller (for the drive shaft out put flange) and a new spring. Also very helpful to have a propane torch (but you can also buy one of those)
It is also possible to put your trans in a suitable gear to get home by using a piece of wire stuck in the filler hole to move the shifting cams. I say possible but I've never tried it. Don't know if I would be able to make sense of this method of shifting.
SOP anytime the trans is opened for any reason is to replace the pawl spring.