Hey Simon. I realize this thread is old and hopefully you’ve had other answers. What has been the outcome? Are you holding the “g” using this alternative way? I’ve seen/heard others use this method. In my opinion it’s already easy to go in and out of G7/Gm. The disadvantage to holding that way is it greatly limits your pinky’s mobility for hitting melody notes, which is extremely important. You can get away with it on a tenor, buts it’s even harder on a concert or soprano. If moving to a guitar, most would say not to hold the chord shape that way because it drops your wrist and adds unnecessary stress.