Now that this has happened I guess they might react a bit differently to correspondence about it.
Also, I feel like SFMTA may not be super-great about responding to correspondence about specific intersections and traffic design (which is not to say that they don't read it or don't think about what people have to say); I've written to them twice about 17th and Sanchez after someone I know had an accident making a left turn onto the Muni Metro tracks, and I never got a reply.
Try tweeting if you haven't already. I tweeted regarding the intersection at 17th and Harrison (before they improved it a couple months back) and they actually created an issue in their tracking system to address it.
The account to tweet at is apparently @SF311. Here's the thread: https://twitter.com/andrewmbenton/status/710485661267075072