I lost 70 lbs on a low-fat, high carb "diet".

And what does that prove?

nothin', nada, zip.

I too am a big fan of Covert Bailey. Calories in vs calories out. "Diets" work (short term) because your food choices are limited and your caloric intake drops.

I've kept the fat off for ~15 years now, but not because of what I eat...my activity level remains high. I gain a bit of weight(fat) in the winter (now that I live where it snows) and loose it over the summer.

I think a better measure of your fitness is body fat % than weight.
Throw away the scale. I like the tight jeans thing too. If they are too tight, eat less, ride more. When they get loose, eat more (but keep riding )

Oh and if your tight jeans are loose in the waist but get tight around the thighs...that just means you are becoming a
real cyclist.