Wow, Elizabeth, I could have written what you've said for my comment, if I just substituted "tall" for "short" and IT for racy rectangle!
I definitely dress for my body shape, posture, and personality. I like to emphasize my shoulders since they minimize my rectangular tendencies in my mid-section, my mother was a bear when it came to posture (she hated seeing anyone slumped over) so I've always stood up straight, and I like to project an image of competence and authority so straight lines and tailored outfits with a minimum of fuss help me accomplish that goal.
It's really hard for me to dress against my body shape and personality. The soft, floaty, pastel, feminine styles just look wrong on me--even to point where sales staff can start laughing despite themselves. But I can pull off a Dramatic Diva look in the evening without any effort. On my body, decolletage looks more dramatic rather than sexy.
I can wear some fairly edgy looks without feeling overpowered by them, but, I think, for me, the opposite is also true--my body shape and personality overpower the ruffles and pastels making those feminine and bombshell styles look quite odd on me.
ETA: And I get what you mean by having a "walk", Elizabeth. I once had a police officer in my class who told me I had the "don't mess with me" stride that they try to teach in a self-defense class. Accompany that stride with the "death stare" that I use when someone is being rude or obnoxious (behavior I won't tolerate in my classes), his assessment was that I'd intimidate most would-be muggers--something that I really don't want to check out! LOL