Is there any reliable way to get the Dead Center - Mall stairwell second floor shortcut

On the Dead Center - Mall portion, is their any way to reliably get the shortcut to the 2nd story toy store window exit? Anything in particular that the director modifies this based on?

Many of the Left 4 Dead 2 levels have director determined multi-path.

There seems to be little rhyme or reason as to what path the director will give you. It's determined by what the director thinks will thrill you the most that time through. However, in verses mode, it will give both teams the same route for obvious reasons of fairness.

Just be glad you don't have to do the some boring old route every time.

Having played that map hundreds and hundreds of times with the same group of players (thus the same relative skill) I can say that it doesn't appear to be based on skill. We seem to get the 2nd story "shortcut" about 50-55% of the time, and the first floor "long route" the rest. I've had games where we were doing very poorly (multiple restarts, deaths, incaps, etc) and ended up on the first floor, and likewise doing very well (no deaths/incaps/etc) on the same skill level ending up on the 2nd floor. It appears to be a random chance of getting either. There are other points in the game where pathways become blocked, yet another path exists, and seems just to make the game a little varied.