Downbearing- pos.front/neg.rear

[David Skolnik]

Greetings,
My question specifically addresses, in a new piano, the oft seen 
configuration where one has significant (.030")  positive front downbearing 
with a nearly equally significant amount of negative rear downbearing, 
(which should perhaps more accurately be referred to as positive 
'upbearing'. Whatever.)  Is there any feeling, among rebuilders, or others 
with first-hand experience, that such a configuration either has 
attributable tonal effects, or has the potential to introduce some physical 
distortion into the board or induce some other type of failure?  If this 
has been discussed somewhere recently, please direct me.

Thanks.

David Skolnik