I did with Kim -- even now she really only tugs because she knows if she wins it from me she will be rewarded with food, but it allows for a good bridge and I think over time it has taken on
some value of its own...
With her she would pick up toys and deliver them to hand already, but if I were to touch a toy in her mouth she would drop it before I reached it...her delivery to hand was dropping a toy in my outstretched hand...we never touched it at the same time and she was very determined to keep it that way...made it hard to tug!
So in her case I clicked for a longer hold, then for holding while I reached, then holding while I touched, then holding while I held, then I waited until she got a bit frustrated and jiggled the toy to show me how well she was holding it and it exerted a bit of pressure. From there it was just a matter of clicking for more and more pressure on the toy, then to only the most pressure such that she would "tear" the toy away from me...only marking my release of the toy on her hardest pulls (of course she wasn't really pulling it out of my hand at this point...) then just went to an intermittent reward schedule so she never knew which yank would free the toy and earn her her prize.
The hardest part for her was bridging into me holding the toy. That said, working through it accidentally laid a nice foundation for a formal obedience retrieve later...something I didn't know about at the time
As an aside, I did switch to spitting cheese for this. It's gross and I don't like it but rewarding from my hand proved to be an added element of distraction while I was trying to reach for the toy and she was trying to stealthfully discern whether the hand coming toward her was going to deliver food
. I could have done both clicking and treating from my off hand but chose not to. By the time we had moved to only marking/reward taking the toy out of my hand I was just using a verbal marker as the precision of a clicker was unnecessary and I wanted her used to the picture of both hands on the tug.