Task switching delay

When running full-screen DOS windows under 98/SE/ME or CMD windows under NT/XP, there is a 2-second delay when switching from one window to another with ALT/TAB or a hot-key. This is designed so that video monitors can re-stabilise at the new refresh frequency. However with TFT monitors no delay is actually required. How can the delay be removed to aid user reactivity ? Is this an undocumented registry setting, or is there a patch in the video driver ?