I've typically gained 3 to 5 pounds from October through January. This year I only gained 1 pound during that period. I gained weight in February due to some restrictions on my diet[*] which limited the variety of vegetables I ate, but returned to 140 pounds without much effort.
I haven't noticed the other benefits attributed to the diet, and I have some suspicions that it occasionally impairs my sleep (i.e. makes me wake up too early) if I go to bed with my stomach feeling empty after a down day (I think this only happens when I'm quite near my target weight). I'm trying to minimize this effect by having a larger fraction of my down day calories around dinner time.
* I had a problem with a jaw muscle which restricted me to soft food in small pieces. On January 31 while eating a thick sandwich, I did something strange to the muscle connecting my jaw to my skull on the left side, and for 2.5 days my jaw was displaced a few millimeters sideways. That displacement went away one night, and the muscle remained somewhat sensitive to stretching but seems to have gradually returned to what may be normal.