Opinion does seem to be shifting in this direction lately.

To be fair, Mike Mew never advocated to "push harder on the back". The back third of the tongue was always supposed to be the foundation for good posture, facilitating gradual remodeling in the right direction. But many folks (including me) naturally assumed that pushing harder in the back would lead to faster results (more is always better, right?).

However, lately it seems that if anything, pushing harder should be done by the anterior portion of the tongue. See Mike Mew's recent (Nov 2020) take on anterior vs posterior tongue: https://www.youtube.com/watch?v=V-rF9uUiq_k&t=1822s In my opinion, this all but confirms the idea in question.

@justdoit

Thank you for that video

I searched more about this, it seems not to be that clear, I found a comment on reddit with own experiences:

"i dont know about this but when i did only front of the tongue for 3 years my orbital rims started to come down and you could literally see the white scelera of the eye show which never before. also cheekbones dropped and eyes became droopy and dark circles appeared. the positive was i gained alot of bimaxilliary projection and the jaws did come forward.

its been 5 months now that im mewing with full tongue and focusing on the back third mostly now and i will not change that no matter what i hear because wat i have personally seen is too big of an evidence that each part of tongue develops a different part of the face.

full tongue will upswing the whole viscerocranium up and forwards and only the front will pull forward the bimaxilliary part and may drop orbital rims down due to the forward pull and no support underneath."

I have a short mid face, because of a tongue tie.

I make good contact with my forward palate, but the tie prevents contact with the rear of the palate.