To my mind, after shooting the gun is either going to be clean or not clean, and "field" cleaning goes into the same box as not clean. If there is any residue, it will attract moisture, and especially if the barrel is not thoroughly dried after field cleaning. What's the gain?

Most everything I have is flintlock, and the lock is right out there where you can't miss a thing, crud and all, if rust begins to develop. I have no problem whatsoever leaving my guns 4-6 hours before getting home and doing the job right.