For a mental reason (dependent upon the person of course), I support cheat meals (and making healthy alternative choices to satisfy sweetness cravings)as some people need this crutch to hang onto as they adjust their thinking to embrace healthier foods--but only to a point.
What's dangerous is when people start to justify it to themselves because they know they are overdoing it but it's so good to have an excuse to make it sound practical (i.e. the metabolism raising idea) or when they don't look long term and really feel they'll live the rest of their life from one free meal to the next.
Ultimately, you will want to take your lifestyle to the point where you don't need a free meal because you are in balance and enjoy the foods you eat, and can simply choose to be flexible at times when you desire it. I think one needs to have a plan in place like making healthy alternative choices of bad foods like: Oatmeal raisin cookies--replace the refined flour, refined sugar with whole wheat flour and (Splenda), or Natural Peanut Butter cookies doing the same replacement idea), and now you have a GOOD healthy choice due to the replacement of the bad ingredients.
One has to MASTER their self when it comes to this and ween themselves off of the bad foods, but I firmly believe that if in days, weeks, and in months, if the person is 95% correct, there is no way its gonna effect them, especially when 1% of the 5% includes self made replacement of ingredients that would normally be bad to psychologically satisfy the sweetness craving.
Breaking weight loss plateaus, can come through manipulating calories and it seems (other than exercise factors), this is the strongest stimulant effecting the metabolism and----not meal frequency.