Thanks LowSpeed. That is good to know. I found a copy of the Adverse Weather section of the Boeing FCOM online (a document we don't have in our library as we have a company specific FOM). While it does not forbid an APU bleeds takeoff after deice, it does contain the Caution that B737SFP mentioned earlier (APU Bleed TO after deice may cause smoke) so this seems like the obvious policy to put in place. As much as taking off unpressurized is an annoyance, smoke is dangerously distracting and probably not the healthiest thing for crew and pax to be breathing.
I'm going to run this up the food chain. Thanks for the comments folks. It's been very helpful.