Every expansion is gear reset so why would "expansion squish" would be so bad?
Healers already got a "healing squish" in Cata anyway.
To get "the squish" at least somewhat right they will need to fiddle even with sub 60 lvl anyway. No one want to have their hp and mana somewhere in classic and BC range!
By the look on the picture Cata blues in next expansion will be somewhere in ilevel of 85 - 90.
No matter that squish in needed and I approved it, I really do not want to have my health and mana in 4.4/4.5 patch dropped by a factor of 15! They will need to just slight increase growth somewhere in 30 - 60 range. I am more inclined to make (BC) ilevel of 85 to become a new Level 60 standard and build upon this formula. And WITHOUT A GAP in stats between content!