Scott,
There I think there is a reason that Tiger and many other top pros have had their clubs made by Miura for many years - I am confident that one of them is the "soft" steel that they use which I think is also 1018.
Maybe it is just mental, I'm not sure but everyone I have ever met who has hit a Miura or Scratch irons says they have never felt the ball come off the clubface the same way. Many also comment that the increase in feel has helped them lower their handicaps fairly significantly and tighten up their dispersion. Again, golf is a mental game. These comments were in regards to both the blades and cavity back forged irons.
IMO - there is a difference between Cast, Forged and Soft Forged - I felt like there was a difference between the Nike Split Cavs and the Mizuno T-Zoids I had - and the Scratch and Miura are even softer than the Mizzies - at least according to my brain.
If given the same shaft and grip, wouldn't the "softness" of the metal be the determining factor in "feel"?
Do you think a more compact blade or CB clubhead is what provides that softness instead?
Maybe Ari can comment - he's the pro on all of this stuff.