I hear you TD. I'm not trying to say that it IS easy, just that in theory it is easy.

The thing is, the theory doesn't change, so it's up to you whether you're going to live the theory, there's no magic bullet - if that makes sense.

Things that work for me:

Get on/off a train stop earlier to build a bit more walking into the day (I catch the train too).
Go to somewhere further away that I wouldn't normally go for lunch.
I have started making my own lunch, after 20 years in the workplace, mind you, mainly to save money.

But really, just much smaller portions work for me because I know that I can't sustain going to the gym to burn stuff off so I have to eat less.