Here’s a video in which Greg explains the two building concept–I believe it starts at about 21:03 in this video if you want to skip ahead. The whole video is useful/great.
I can’t really advise on how the 2 building concept works as I did not have playing commitments to tend to, so I dove completely into playing a new way and experimenting.
But my understanding is that gradually, our brains develop new neural pathways based upon the new sensations and one day we no longer have 2 ways of playing but one optimally efficient way.
Hope that helps, FWIW, my $.02, etc. Happy Holidays.