TBH
MMI is nothing to be afraid of (i've done them, they are sorta fun, being 100% serious here)
and if anything they actually favor students whose first language is not English
MMI are mainly tests of LOGIC and Critical thinking, and problem/communication skills of course
but to say they are better at weed out socially inept students could not be further from the truth, (yes anecdotal evidence, I'm in Canada and basically ALL health professional entrance interviews utilizes the MMI)
each MMI session is short and to the point, there are NO Conversations, No small talks, and rapport building skills are much less emphasized and factored into the evaluation
just to give an example (a typical MMI station at my school would begin like this: interviewee reads question posted on the door for 2 min, bell rings, him/her enter room, shake hand with interviewer, both sit down, interviewer asks "did you get a chance to read the questions?" Guy/girl says "yes", interviewer says "k go".
what MMI are good at, (imo) are making the interview process more objective and "fair"
everyone get the same set of questions, you get multiple first impressions, you are evaluated based on an aggregate average of multiple interview assessments
perhaps im just being cynical, but lastly i should point out that [mind you this is solely imo] that the main reason why schools are implementing MMI's is to save COST. it is Much more less expensive and logistically easier to hold MMI sessions than the tradtional interview methods.