Staircase

[David Hairston]

I'm interested in creating a paradigm involving a staircase method to detrermine a threshold.  Has anybody done this or have an idea of how to do it in E-Prime, short of hard-coding the entire thing in E-Basic?
 
In particular, I'd like to quickly narrow down the temporal threshold for a temporal-order judgement task, in which S's simply report which of 2 visual stimuli appear first.  Thus far I've done this via the method of constant stim  by just varying the Duration variable of the pause between them... but boy, how ineffecient...
 
Any suggestions would be greatly appreciated!
Thanks