Yeah, good point. Changing out that washer will mean draining over half the oil. It is a bit fiddly to change out that washer and doing it in a rush would not be fun.Don't get me wrong, I am not recommending to not use new crush washers. I have been to lazy to order/ buy them for my oil changes and have gotten away with it. For his operation it is going to be much easier to loosen the bolt until some oil starts coming out than to take the bolt all the way out to replace the washer.. He will likely be fine just re-tightening it and getting a more controlled flow to get just that limited amount of oil out.