I will agree with you that driving/healing/casting and trying to keep everyone happy and at a good pace is difficult on the hands/fingers/wrists. Seems like a few people agree here, and some do not.
Good place for some constructive discussion I would hope.
I do not heal enough to really feel like my vote counts, but when I do heal I prefer not to drive, it's just too much chaos and either my drive speed suffers or my healing capability suffers, both are not acceptable to me. I can see how this (or something like this) would be very beneficial to the people choosing to heal others. I give credit to those that do, they are an important part of a good team.
I am undecided but would like to see more opinions on both sides of the fence, especially from those that actually heal a lot.
e: If I had one of those fancy programmable gaming keypads this probably would be a lot easier, but with the "stock setup" so to speak, it can be a nuisance.
I chose to just not be a healer. (as bad as that sounds, again I am very thankful for those that DO heal)

well im not always driving, but I find ls a simple relaxing game that I would like to play with my hand on my mouse only while not diving ofcourse!