"People under time pressure don't think faster." - Tim Lister. Tom DeMarco calls this piece of wisdom, "Lister's Law", in his book, Slack.

Consider this variation of Parkinson's Law from Peopleware (DeMarco and Lister)(3rd ed.), "Organizational busy work tends to expand to fill the working day." Unlike Parkinson's Law, this one has studies to back it up. Pressure doesn't work on knowledge workers.