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Alright, so that was a bad solution as well since it broke tab indent/unindent functionality.  Messing with tab and escape functionality is too finicky for me to bother with.  I'm just gonna remove all the tab autocomplete associations for now and use ctrl+space instead.  I like Sublime's matching algorithm and its dropdown menu over Textmate's approach, but loved having a single-keypress autocomplete shortcut.  ctrl-space isn't too much more movement, however, and it doesn't break any preexisting tab or escape functionality.
Actually, I've changed my stance on this.  Remapping tab to pull up the ctrl+space style autocomplete dropdown is nice solution to this.  A single keystroke followed by enter is quite adequate, I think.
This is the one thing I miss about Textmate so far.