Well here's my take. Over the summer I took Orgo 1, Orgo 2, Human Anatomy, Human Physiology AND Kaplan. I got two A's in P&A, an A in O-lab, and a B+, and B in O-1 and 2 respectively. DAT is on Monday and I've been getting 20's on the practice tests. SO, YES, it's something that can be done. Keep in mind that I litterally had NO life for the last couple of months but I tend to do really well when I have everything going on at once. Also, the courses I took were EXCELLENT prep for the DAT so that limited how much of everything else I actually needed to study. We'll see how I do on the real DAT, though.
I'm also going to be the outspoken one here who actually believes that Kaplan was worth the money. Do you know how much you're going to be spending on licensing exams!?? Plus, if you're going to try to mix DAT studying with schoolwork, the class was invaluable in keeping me on track. Treat the DAT like a regular class and then figure out what you can handle from there. And the people on here who claim they are studying 8 hours/day for 6 months either have very poor retension, very poor recall, or are lying. There's no reason you need to spend that kind of time just on the DAT!
Anyway, sorry for the rant. I'm on a short fuse right now with the test coming up. I just want this summer to END! Short of it though, is that you can do whatever you want to do if you dedicate yourself to it. Good luck and PM me if you have any questions.
Mack