Not exactly. The first round of cuts at STL were in November 2003, transitioning much of the operation to what was then known as American Connection (operated by Trans States and other non-wholly owned by then AMR Corp operators). As of summer 2003 the combined operation was approximately 400 flights which dwindled down to about 200, many of which were operated by American Connection. Cuts continued on a few flights and cities here and there but things remained relatively constant until 2006/2007 when there was actually a slight resurgence of the AA operation and reintroduction of mainline service to a number of cities (AUS, MSY, RDU, and SAT if memory serves me), along with added frequencies on other routes. When fuel prices started to run up again there were several more rounds cuts. By late 2008-early 2009 it was down to about 100 daily flights, until AA pulled the plug effective April 5, 2010 and the only remaining non-hub routes were BOS, DCA, and SEA. BOS has since ended, SEA is operated by AS and DCA is now operated by Republic E75s.

DLs actions at DFW were independent of AA's in STL. The only connection is AA did add some additional DFW flying when that capacity was freed up, but in the grand scale of things at a hub the size of DFW it wasn't a sizable increase. Furthermore many of the TW aircraft that served STL left the fleet, 717s went first, 763s went fairly quickly, some S80s stayed around (and remain active today) and the PW 757s were returned to their lessors in 2006-07 and now operate European routes for DL.