HOLY FUCK, THAT IS HOW YOU DO A T-BAR ROW? WOW!
Well, that's depends what you are doing. If you are showing off like this ape, you can do it that way, but if you are training your muscles, there will be more benefit with longer range of motion. Stretch is a part of the T-bar row and if you eliminate that with short range of motion, it isn't T-bar row anymore, it is jerking off. You can't make your lats wide and full by jerking off, so do your math.