This Brooks B17 Imperial comes pre-laced. I can't give much of an opinion yet with only 150 miles on it so far. I'm just showing it to illustrate the factory lacing. I have another leather saddle, a Selle Anitomica, that is back at the manufacturer getting laced. It is a free service by the company.
However, I've had 30 years experience on this Brooks Pro. In my experience with this saddle, I can say that dozens of applications of Proofide did not significantly soften the leather. Most of those treatments were applied with the aid of a hair dryer.