The difference is - prospectively - a rail trip in a two-turn race on a fair track (i.e a track where the only bias is the shortest way around) sets the horse up for the possibility of a perfect trip.

Whereas a horse 3W on the clubhouse turn on the same fair track (i.e. a track where the only bias is the shortest way around) does not have the possibility for a perfect trip.

There is no more perfect illustration on planet Earth than the 2019 Belmont Stakes. Reverse the trips of Sir Winston and Tacitus and Tacitus wins by five lengths - geared down.