If you're a visual person, maybe comparing all of this to a gradient grayscale can help. In your OP, you separated CDers between just plain CDs, and trans CDs. First, you need to know that the word "trans" means to cross over. To some people (the TSs), it means to permanently cross over (full transition and live full time). To others, it means to dip their toe in and pull it out again (repeatedly), while for still others it means to jump in, swim a little ways, and then come back and climb out again. To people who are not trans at all (the men who do not crossdress) it means to not go near the river, in fact they do not even know it is there.
Anyway, in your eyes (and in many other members' eyes), the spectrum is as follows:
Garden-variety CD => CD with a degree of feminine identity => TS
(White => Gray => Black)
During the 1960s, a researcher (Dr. Harry Benjamin) came up with a six-step gradient describing the needs of birth males who crossdress, from males who just puts on women's clothing for kicks (usually this is purely sexual), to someone who needs to transition. So Benjamin's grayscale looked like this:
White => LightGray => LightMediumGray => DarkMediumGray => DarkGray => Black
But, in reality, the spectrum of differing needs is a full gradient, with a million shades in between the white and black. This means that unless a male is a pure fetishist (has absolutely no desire to dress for any other reason than sexual gratification), there is a degree (to varying intensities according to each individual) to express innate femininity, that non-trans men do not experience. Men who do not crossdress are not on this gradient.
The clothing helps to get in touch with inner femininity, but it is more than just the clothing, it is also transforming the total look with wigs, makeup, breast forms so that the image in the mirror can approximate how the CDer feels inside, even if he is not transsexual and has no wish to alter his body in any way or to live full time as a woman (which would be the black end of the scale).
Here's an older post I made, just so you can see the Jpgs of the gradients:
http://www.crossdressers.com/forums/...=1#post2853849