Look at how New 3DS worked out? People were not happy and actually didn't give to shits about it. They had one or 2 games that would only work on New 3DS.
That's the issue. And seeing that Patrick was able to get a few "Sighs" with developers scratching their heads, seems to show that not even they are looking forward to having to target different specs.
As SneakersOS was saying in the XBox thread about this similar issue. I don't see how this doesn't ad more work for them. Regardless if performance might be better with a more efficient CPU/GPU, THEY STILL have to make the game run and look good on the base PS4. There are too many people now that own one. It makes sense to do this when sales stagnate and all developers are showing they can't run their updated engines and current configs on the current console.
It does not make sense to put one out now. Unless PSVR needs this upgraded/refresh to actually run the games properly, that's a whole another conversation alone, that will piss and confuse tons of people off.
I'm in the boat that the ends don't justify the means in this scenario.