LOL That's one practice i never considered. When necessary i always took
the trouble to wipe it with clean toilet paper. Yep, new stuff not used already.
That's a long time to get rid of it, but guess you did all you could at the time.
I have a faint memory of maybe asking dad at the time if iodine might have been better used earlier and that he said no,
that it was only good to be used where there was moisture from fluid. Maybe. If i ever had it again i would try it earlier.
Just out of interest, to see if it worked.