Feelings ( slamming backchecks)

[A440A@AOL.COM]

Greetings all, 
Can we talk about feelings? 
  I have been thinking about backchecks. It seems that all the lore for 
regulating them, and the attendant tail carving to match, have been with a 
view for mechanical efficiency in the checking.  (Making sure that the hammer 
catches is important, imho, for without it, the repetition spring is not 
cocked and the resulting key rise on release will be slower). However, is 
there more refinement available than just making sure the tail is always 
caught?  I think so, and it results in a slight improvement in "feel".   
   Specifically, the feeling of the hammer hitting the check, as it relates 
to shock waves in the action train.  This became a factor as I regulated an 
off-brand piano that had had hammers replaced at some point.  It felt hard, 
as in,  more than "crispness" in response.  The hammers checked, but did so 
by digging into very hard leather on the backchecks.  On moderate to soft 
play, I could distinctly feel the contact.  By shaping the tail into more of 
an arc, and bending the backcheck to intersect more properly,  there was a 
noticible "softening" of the touch. The hammers also checked slightly lower 
on hard blows, whereas before, they checked at the same height, no matter the 
 force. 
     	This effect was slightly less than the change wrought by say, 
mis-adjusting the up-stop rail, and about on a par with replacing hard 
key-end felt with softer material to mask the damper-lift.  
   Anybody investigated this avenue farther than my three cups of coffee?  
Regards,
Ed Foote