I have many mechanic friends and many of them need exercise more than I need a catastrophic tranny failure in flight
When it comes to a mechanic (engineer) climbing a mountain with a tool box tucked into his hip pocket......or me setting on the ground with a cup of coffee saying "Sorry-O!"......as 170' rightly says....guess which one wins!
Granted the one time this sort of thing happened....it was because the aircraft would not start and was put down to a dead battery. The Engineer and I toted a battery.....one of the bulldozer sized things the Alouette III required....up a mountain to where I left the helicopter when it would not start. When I gave it a try before we changed the battery.....she fired right up.
Said Engineer said that except for me having carried half the battery up the mountain with him.....it would have been a fatal event.