Because I came from a dog training background when I got really into horses it seemed so sensable to carry on talking.
My first real experience was when I broke my pony to drive. He 'learned' left and right as well as whoooo, and all the transitions upwards and downwards just from spoken commands, it was so simple.
I like to talk to my horses I feel that they respond very well to words, and soon 'pick up' the words we need to use.
And this gets better as the horse gets to know you better, my welshie knows ''do you want a sweetie'' [ he stops dead]

Spotty 'knows' ''and canter'' and ''come, come, come'' for sideways.
and sadly yes he too knows ''sweetie''..... [ im such a bad mother!]