I've tried after experiencing a sliding support hand issue with the more main stream grip.

it didn't help

Apparently, I need a +45* to stabilize my support hand and stop it from sliding.

Who needs a second hand?

 I didn't know it was a type of hold (let alone from the 80's) but last time out with my P938 my left index finger wound up there a couple times.  It's a small pistol.  I kind of liked it but tried to acquire without it.
the issue never came up on a G17 after all these years.