I have thought for a long time that when my cleaning patch is too wet, my cap lock rifle is more likely to misfire.
The trick is defining where 'too wet' begins. But sopping is definitely too wet.
If I clean after every shot, then I'm not afraid of pushing much fouling down to the touch hole - because there isn't much, it hasn't built up. (Is your touch hole right on top of your breech plug? That may be a reason your mileage might vary.)
When in doubt as to whether your vent is open, push a wire into that touch hole.
But I like to clean all the way to the bottom for safety reasons: I have been there when someone else's gun flashed on loading, and he was burned. Not just burned a little, $400 hospital bill.