hi dookbloo,
for waitlist movement to occur at TMDSAS schools, an accepted applicant to a TMDSAS school must have decided to go to a non-TMDSAS school, or have decided to defer entry for one year.
let me illustrate this with an example:
john is accepted to UT-Houston and has been holding a spot there since february. yesterday, he was accepted to his dream school Harvard and decides to give up his UT-Houston acceptance. suzy, who is on the UT-Houston waitlist, is accepted off UT-Houston's waitlist in order to fill the spot vacated by john. suzy, however, has been holding an acceptance to TAMU since february. she gives up her TAMU spot, and now TAMU now needs fill in suzy's spot with another student, who will come off TAMU's waitlist. etc, etc, etc..
ultimately, the process of texas school waitlist movement depends initially on an accepted applicant choosing to attend a NON-TMDSAS school. it is in essence a trickle-down effect.
i decided to attend Tulane in New Orleans.
i hope i have not confused you! good luck!
askoogi