While I agree that one should not scrutinize match lists, I do believe that there are general trends that can be seen over the years. It is easy to see that many top-ranked schools generally post match lists with a higher percentage of graduates matching to high-powered programs compared to lower-ranked schools. Sure, people may choose certain programs or certain geographic locations for personal reasons, but these cases should ultimately even out if you look at match lists over a few years when comparing schools. While I do not promote agonizing over match lists, I do believe that there are trends that can be seen.
I do also find that the effect of "school prestige" is consistently downplayed on these boards. While I don't think that "school prestige" is the end-all, be-all of residency application, I do think that it plays a bigger effect that many people give it credit for. True, people can match into top programs from any school as long as they do well in their rotations and ace their boards. However, when trying to rank a group of equally highly-qualified applicants, "school prestige" can easily become a distinguishing factor and may be a difference between being ranked 8 or 9. The question that I think you should ask yourself when choosing medical school is that when you apply for residency, will you be bothered by the "what if's" if you ended up choosing a lower-ranked school but not matching at your top choice program? It is impossible to know exactly how much "school prestige" plays in the residency match process, and program directors would likely downplay its effects when officially asked. However, to say that it has "little effect if at all" is simply not true.
In addition, I think the biggest effect "school prestige" has is actually with those who are average to below-average in their medical school class. Middle to bottom third students from top schools often match into decent academic programs riding mostly on their school names. At the very least, they would have a much better chance staying at their home institution. This effect is often easily observed by looking at the residents list of many academic programs (particularly large programs). It is not uncommon to see a trend where residents from lower-ranked med schools are usually AOAs while those from higher-ranked schools are not. I think that this is an indication that "school prestige" plays a role in this process.
I do understand that many of my points are based on generalizations. However, I do think that they are useful in showing these trends. I am not putting down any school or students attending any school. I do believe that any student from any medical school can match into any program of any specialty, as long as he/she shines during medical school. However, I think that in a head-to-head comparison of similarly-qualified applicants when programs formulate rank lists, those from higher-ranked schools might have a slight leg-up. I also believe that "school prestige" does cast some sort of "safety net" for average or below-average students at higher-ranked schools. Therefore, I think one should take these into consideration when choosing schools.