I have read your article in The Art Newspaper about Sotheby's Institute MA Program and agree with you completely.

My MA in Lisbon has a partnership with Sotheby´s and I have also participated in other of their courses - Could not be more pleased with the Institute. 

Like you mentioned the school is, indeed, very good - Well-structured programs, high quality classes, really good teachers and so on.

Nevertheless, I would like to add the following, regarding to the expensive fees:

• Sotheby´s Institute students have many visits and lectures outside the school. Also many visits to museums, auctions, exhibitions, galleries... (Which is fantastic!) Usually the school take care of all expenses (tour guides, entrance tickets, trips - Last time I was at Sotheby's we had a bus and a boat trip that were totally organized by the Institute) This, facilitates students lives and solves logistics problems, but it is an additional economic burden to the school - Not sure if other schools do the same (in Portugal, certainly not).
• Sotheby´s Masters students have access, during (I think) a week, to personalized support in order to help them to develop a plan on how they should approach the job market. I suppose this help includes: tips on how to write resumes; motivation letters; approach on interviews. To decide which type of job position is best suited for them to start and to pursue their professional goals. They provide a "guide" with places where to look for jobs and (I guess) they even make the first approach for you. They care and want to help their students to find a job, which is, obviously, good for the school as well. 
• Sotheby´s Institute have one of the best networks in the art world. Certainly, their employability rate is quite high and, I guess, that is also included in the $ 75,000 fee.

Sometimes I wonder if instead a Postgraduation in Art Connoisseurship + a Master in Art Business (a total of 4 years + 5 in college!!!) I should not have gone for a one-year course at Sotheby's... The answer is, probably, yes...