When I was a child, I had a normal rounded hairline. In my teens, I developed a pair of receded patches above my temples which for years I incorrectly referred to as widows peaks, and for which I've never found a correct name. In the second photo at right, I've roughly scribbled my natural hairline in cyan. Yes, that's me without makeup ~ Urk!
While I was at University, I grew my hair long, but never went out crossdressed, in part because I wasn't able to effectively disguise my hairline.
After getting my hair cut short as part of a partial purge to try to sustain an unworkable relationship with a woman who absolutely rejected my crossdressing (who was also a cougar almost 10 years my senior), I bought a wig and stopped thinking about going out without one.
To avoid having hair showing that contrasted against my wig, I took to shaving up each side of my forehead to remove that hair. As I bought different wigs, the shape of the edge of the wigs varied and I shaved slightly more hair, until I ended up shaving an almost straight line from the top corner of the ear to the outside edge of the bald patch, as shown by the green line on the photo. By taking that hair off, I actually made the hairline less noticeably receded, but still not good enough to go without a wig.
I think that it was in late 2010 that one of my friends from the cafe nights, Jenny, mentioned that she prefers her hairline to be higher in the middle of her forehead than it is naturally, and that she shaves it to raise the line. Like the sides, I had already been taking a little bit off there to suit wigs that didn't come quite far enough forward, but I hadn't considered taking considerably more off until Jenny mentioned doing it on purpose.
There is, of course, a compromise to be made. On one hand, the hair that I remove means less hair in my already sparse fringe, but on the other hand, the raised line (shown in lime green in the photo) means that the hairline looks more rounded and that the thickness of my fringe is more even because I've removed some of the thickness from the middle while not altering the edges.
The last photo here was taken after this week's cafe night. I simply brushed my hair back to reveal the makeup, while the first photo is how it looked with the fringe brushed over it.
Does that qualify as a comb-over? :P