I'll agree it's not designed to be deadly, however, neither is a Baton, it's designed to incapacitate, possibly cripple, but not to kill.
I know American cops go through a LOT of baton training, on how to reduce the possibility of permanent damage etc, a baton, like a taser, can be used to bring down someone who is resisting arrest, or is running away if you're a good shot, but, if you saw someone being beaten with a baton while 5 other Policemen held him down, there'd be no question that it was out of order, occasionally Policemen may want to put the boot it, and occasionally I wouldn't blame them for doing so, but when you are Policeman, one boot is crossing the line from upholder to abuser.
Now, of course, the world doesn't work like that, and I've wandered a bit off course, but the crux is that a Taser should be treated like a baton, it's a non-deadly weapon used to bring the person to the floor quickly, with as little risk to them and yourself as possible, it's not something to be used on an already pinned, but scared or struggling arrest, I'm afraid the Police should really be relying more on Handcuffs and Hogties for that.