That was kind of the situation for the 2700 vs 2700x. The boost clock algorithms reacted very differently to each processor, even though both were pretty regularly able to hit 4.1-4.2 all core OC. The 2700 natural behavior constrained it a lot more to keep it much lower on power draw, but you could force it to draw as much as a 2700x. I think that's what the TDP diff is here. The behavior in how aggressively it automatically pursues that auto-oc.
Yeah. 2700x does this so well that it's basically pointless to manually overclock.