I didn't find Paul McKenna's book and CD that great - because I would willfully rebel against the messages!!!!
I had hypnotism for weightloss once before and it got me to understand when I first started comfort eating and why, but it never helped me then move forward to stop it happening in the future.
The only think that HAS re-educated my thinking around food has been the LL counselling and reading Gillian Riley's "Eating Less" book - because both have given me pratical ways to deal with the issues that cause me to overeat!