I'm not trying to pick a fight or be argumentative, but I do disagree with the attitude that those interested in biomedical research should just stick to a PhD. Also, I agree whole heartedly that MDs can do great research (see the final sentence of my previous post). But, I hate to see someone truly interested in both degrees discouraged from pursuing both. My experience is as an MSTP graduate from a school in the top 25 for both research and clinical med schools, but it is a state school so my opinion is tempered by that particular environment. Here are some additional thoughts.
"More and more from what I've been seeing (as a new professional in this field) is that research is very important for a clinician to understand the basic science behind many of the achievements of the last 10 years... and research experience even for young med students is being valued as a very important piece of that education." I couldn't agree more, it is important for clinicians to understand basic research. I hope that med schools are moving towards some research experience, but I haven't seen it yet and I'm not sure when it would fit in outside of an extra year of school (maybe that's what you mean). As it is, clinical courses are added regularly, and this year's M1 has more coursework than I did back in 97-98. Plus, at a state school the number of students interested in research of any kind, other than a summer project to put on their CV, is extremely limited. Many students do these summer research rotations, but it is completely elective. There may be a trend towards more research in some of the top tier schools (doesn't Yale require a thesis?), but short of an extra year which is voluntary, I don't think many med schools have this as part of their curriculum. I'd certainly be interested to learn of those that do.
"But I wouldn't go so far as saying they would be that supportive of people dropping out for a few years to complete a Ph.D." This is my experience, and seems to be the experience of other posters. Yes, I use anecdotal evidence of two students among the hundreds during that time, but from what I know they didn't have much difficulty scheduling it. Although I have no inside information, I just don't see why a med school would object. Maybe we're dealing in semantics of "supportive" vs. tolerant.
"MD/PhD programs are not for everyone, and while there is some recognized deficiency in the number of people with both degrees, it should not be presumed that MD's cannot perform important research. It's never going to be easy, but it's not easy for Ph.D.'s to get gainful employment as researchers either." Again, I couldn't agree more with your first two statements. I'm not sure about that last point and how it fits. In some cases, it's actually easier for an MD to do research because of access to clinical specimens, data, etc. There certainly are great MD researchers, but the experience of a PhD makes it easier to transition into research, after all that's what the training is for.
"That said, if your heart really is in biomedical research, consider just doing a Ph.D. You'll be less in debt and at least in the short-run less stressed in learning the material (though it will still be rather quick). But MD's and other medical professionals can perform and do research without that degree because there are other opportunities to pick that up later on. And you are encouraged to do so." Maybe we can just agree to disagree on this point. I think someone truly interested in biomedical research would be well served by an MD. I can't say my PhD was less stressful than my MD, just different. I think earning the degrees together, if possible, helps integrate the two in a way that isn't possible any other way. I'm not completely familiar with the residency/PhD or fellowship/PhD type program, but from what I hear research time is never as protected as it is during a "true" grad school experience.
Finally, don't take it that I think everyone interested in research should pursue a combined degree. In most cases, I think a summer project or something similar is more than enough experience to help foster an appreciation for basic and clinical research. My main point in posting is that soemone already on the path to an MD (or considering it) who is also interested in having research as a large component of their career shouldn't hesitate to look into PhD options.
I'm eager to hear your thoughts.