Grimsy,
Did you perhaps not bother to read all the replies above yours? If you did, what on earth led you to assume we all had it wrong?
If it was an honest mistake, here's some information:
TC lockup is a device for saving fuel when you reach "cruising speed", i.e. the load is quite low, torque multiplication is not required, and economy can be had without penalty to performance.
The power button has the opposite effect. By delaying gearshift to higher revs, you get more power at the expense of fuel consumption.