my god is that still doing the rounds when i used to go up to i.m on courses they were all laughing about that procedure and how it gets you an extra 20bhp needless to say it doesn't work, the guys in training school will tell you all the ins and outs of why and what not but all it's good for is getting your brakes hot!!
iain is correct just go out and vary your driving it learns within a few miles all it's ignition timing and curve so if your only doing a couple of miles a day it's probably still on choke!
do a reset and go for a blast!