Should I submit an additional letter of recommendation?

I know that on their website, MIT says that most students do not submit an additional letter of recommendation; however, I have a potential letter of recommendation that could put a lot of weight into my application. My mentor for my personal research project is a dean at a decently renowned university, and she agreed to write recommendations for a few colleges for me. My STEM teacher, who is my advisor for the project, also wrote a letter of recommendation explaining the project and all the work I have done thus far. Is it still beneficial to send the additional letter of recommendation from my university mentor? Or would it seem too redundant?

You will get a variety of answers (opinions) on this. Here’s mine.

A number of years back I knew someone who worked in the MIT admissions office. We once discussed this exact question. She replied saying those working in the admissions office work very long hours reading applications. When an applicant sends in more material than what MIT asked for, it makes the reader have to spend more time on that application.

For some readers she said, human nature kicks in and it can hurt when an applicant doesn’t follow directions and makes more work for them.

I may have gotten that advice years ago, but I’ve never forgotten her point about the importance of being respectful of others time.

YMMV. Do what works best for you.

I had two interviewees last year who decided to submit supplemental letters of recommendation.

One submitted a recommendation from his summer job supervisor, who oversaw his work on autism emotional outburst and mitigation software.

The other submitted a recommendation from her research supervisor (I think it was biology-related at a certain very reputable somewhat nearby university).

Shrug. Both were legitimate and good reasons for submitting supplemental recommendations. One was admitted and the one wasn’t. However, the one that wasn’t admitted was admitted to that Ivy League School that has a color as a name.

I think this is going to be your judgment call.