'RS' I think yr drawing a very looong bow there with ref to mech devices to start engines is the same as hand swinging. Yr connection to both being technically one of the same are miles apart as a starter motor used for starting an engine is far safer than the 'armstrong' method hence we have them in the first place today! The core subject here is safety or just how safe is it with hand swinging & in my opinion ( & that's all it is) hand propping is damn dangerous & should be avoided at all costs in today's modern A/C.
'MIHC' you too are drawing a loong bow with ref to yr prop face. Whilst you are technically correct as far as the operation of a prop goes it's generally accepted that the front of the prop is the part that you face whilst holding it during the dangerous act of hand swinging same.
Still at the end of the day it's about choice. Being able to hand start an engine doesn't mean yr any better than a pilot who can't or doesn't want to, the latter may simply want to improve his chances of flying the next day
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'slippery' I'm with you
Wmk2