duna,
You're absolutely right; that phraseology should suffice, but often wasn't enough. The qualifier seemed to emphasise that the urgency of a speedy takeoff was paramount. Once I started using it, I can't remember having a problem.
As for issuing an abort to an aircraft doing 100kts+ (if this was the case), you're starting to venture towards V1 territory anyway, so why get yourself and the pilot into a very sticky situation?