Goro, I think that this is one of those areas in which your experience varies due to being at an osteopathic school (maybe b/c you welcome so many applications from individuals who are in a variety of circumstances that make them ineligible for or make it impractical to obtain one). I have seen several threads in which you have said it's no big deal not to have the support of your school's committee in spite of others chiming in to disagree. Now that
LizzyM has weighed in on this, please consider that similar to physician LORs, this is one realm in which allopathic and osteopathic adcoms might weigh things differently.
I think enough MD programs are like LizzyM's that it does SDNers a disservice to call it a myth or suggest it only matters at schools where it is explicitly required -- many allopathic programs make it clear that it is
very strongly recommended (and we wouldn't ignore strong recs in just about any other part of the app). The wiggle room that exists seems to be for non-trads and people with extenuating circumstances, but they are often expected to explain a missing committee letter in the secondary. If applicants from one's school are known to typically have the letter, lacking one must at least give pause -- did the committee not support the applicant? why? was the applicant unable to provide materials to the adcom in a timely fashion? what does it say about the applicant that he's choosing to apply without the letter instead of waiting a year and applying with it? I don't know
how much it could hurt an applicant, but I really don't want someone here to be hurt by applying without a letter instead of waiting a cycle to get one, b/c your advice and that of all the adcoms on here is taken very seriously by the pre-meds.