Yep, I have it and nope, it is not contagious...portion distortion.
After 9 weeks of being on my own plan of eating, I am starting to get better at portion sizes. Initially, unless it was basic counting, I was not good at portion sizes. So, here is one of the things I started doing. Take an item whose calories are based on weight and not a number (i.e. 7 crackers is a serving = xx calories). Try to guess a correct serving size (or the correct weight) for your "allowed" meal. Then weigh it and see if you are close. I was always having to cut extra off or take some away. Having to take away or add more has helped my visualization of the correct amount/volume.
I must say, now when I am eating certain items, I think back to how much of it I used to eat and realize how grossly distorted my portion sizes were (though I really don't think I was even paying attention at that time).
I found a great article on Spark People, The Bikini Diet, which is all about portion sizes. One part of the article has the analogy of using a bikini top for your portion sizes. For example, on a 9 inch plate, dinner should consist of one bikini top cup being meat or beans, one bikini top cup being your starch and the bikini bottom is your vegetable and/or salad. Now, if I picture what my bikini top and bottom would be, STOP, let's not go there, remember, it is a BIKINI (haha). Here is the link for the article:
I hope The Tortoise's Weigh has given you some ideas about portion control (if you have any issues with it)!