I've only had 4 or 5 flinters but have never had fouling get into their innards, maybe just lucky, or because I never fire more than around 100 shots in a day's shooting.
I do remove the lock for cleaning as it's easier to clean when it's off the rifle, using a toothbrush (my wife's) to clean the fouling around the frizzen, cock and pan. After 100 or so shots, it gets a bit 'fouled'.
I then wipe the excess water from it, then blow the rest off with compressed air- then spray liberally with WD40 to get the rest of the moisture from the crannies and nooks around the lock''s parts. I wipe, then blow the excess WD40 from the lock & reinstall. Total cleaning - barrel and lock removed from the stock, barrel cleaned in a pail of water, same with the lock, dried, oiled and replaced - maybe 15-20 minutes & only 4 to 6 cleaning patches needed.
To "properly" clean a modern rifle, usually takes longer to much longer.