The cut & glue trick was a common flat rate shortcut, back when mechanics routinely squeezed 60 hours' or more labor time into a 40 hour work week. It turned an hour's worth of work into 15 minutes or so, and if the diagonal cut stayed at the top of the tube- - - - -I've never seen oil run uphill!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!