If your timing isn't right or cabbies are out of course they are going to kick you in the arse and of course I have had my share of kick backs with 40 years of owning my Norton but now running a Joe Hunt maggie and tuned right I never get any kick back and it normally starts with half a kick and having a longer kick lever all helps, but I have seen some get hurt very badly from not kicking their Nortons the right way, usually new owners who have owned Jap bikes all their lives and don't know the secret of starting a Norton, it is funny to watch sometimes but not funny when they get hurt and some have even sold their Norton because they could never get the hang of it.
When I first brought my Norton when I was 17 years old and skinny and light as a feather, I soon learned very quickly in how to kick start my Norton, I have no problems with kicking my bike with thongs (flip flops to some) or even bare foot, don't know about the hand trick but, but I do know my Norton will start on the first kick every time.
Ashley