There does seem to be a discrepancy somewhere along the way.

Wallingford:
Team Professional S
177x245
Fitness
177x245

Brooks England:
Team Professional S
170x245
Fitness
170x245

But just out of curiosity, I'm gonna line up all the saddles discussed so our eyes can do the judging. Measurements off www.brooksengland.com

B17 Special:
Width: 170mm
Length: 280mm


B 17 S:
Width: 177mm
Length: 245mm


Team Professional:
Width: 160mm
Length: 260mm


Team Professional S:
Width: 170mm
Length: 245mm


Fitness:
Width: 170mm
Length: 245mm



Who knows how they decide to measure the width saddles, but there's definately a difference in shape.

Speculations...