Originally Posted by
FBinNY
If the brake shoe is moved farther from the fulcrum and the cable isn't he'd lose leverage and would pull less cable for the same shoe movement. If the arms were lengthened to maintain the same approximate 3:1 cable:shoe distance the cable pull for given shoe travel would be the same.
I actually ended up throwing some math on the issue - but you're right. If the brake arms would have had to swing through the same numbers of degrees he'd have been all out of luck, but for the same amount of pad travel it all works out.