Even though the original question was about Shootfighting, considering it in terms of BJJ is a valid way to approach it because in many ways the entries are similar. If anyone is interested in this subject but has never experienced it on the mat, you might want to give it a try. I don't advocate it either way, just saying if you want to "know" then go try it. With someone good, a BJJ black belt for instance, you probably won't be able to do any atemi, or low kicks etc. This is just fact - they know what they're doing, and they train for it.
Many people found this out in the early days of the UFC - but none of them studied Aikido, unfortunately, because Aikido does, in my experience, offer some potential ways of dealing with this.
Not if anyone thinks it's a cakewalk, though. Attitude is a huge part of it.