I have been a longtime practitioner of Striking Arts, but when I took BJJ a couple years ago, both of my best friends enrolled with me. The two of them are female--both athletic, and with no Martial Arts Experience. One of them was not very committed and had trouble remembering anything more than a bare minimum, but I feel she would have been such in any art. The other, however, surprised even the instructor.
My friend in fact turned out to be very skilled, and rarely lost, even to practitioners with much more experience. Generally she also gave up 50-100 pounds on these guys. My own judgement as an instructor was that her skill came from the fact that she's completely fearless, and will charge into these guys with minimal hesitation.
Well, without rambling on and on, half of the women in the group were extremely good, (it was a co-ed class), and I mean good enough to take on the tough guys. To my friend's credit, she has also jumped right in during sparring sessions among myself and my other striker friends.
I think she offers strong proof, in my experience, that it's all about attitude. Everything else is little details.
Yours in the Arts,