Since this is in the advanced section, I would answer that breadknifing does not mean only bringing the razor to straight....
It can can used on a smiling razor also, or to bring back the smile...
I would suggest that you take a magic marker and start at the thinnest point on the blade, and draw a line from that point to the toe, then to the heel using the smile curve that you want.... Now look at how much metal needs to be removed to accomplish this and make a decision as to whether that would help or hurt the final outcome of the razor....
This might actually need to be done with a Dremel or grinder to have the proper geometry...