At another Canadian carrier, operating the -800 exclusively...
Our deicing checklist specifically states that if performance requires a no engine bleed takeoff (after de-icing), to use the unpressurized takeoff procedure found in FCOM supplementary procedures (section 2).
The reason for this is to avoid the exact situation you've described.
Last edited by lowspeedaluminium; 1st January 2016 at 00:25.