>Has Peter Svensson written any papers et-cetera on log sweep >vs MLS vs TDS? If so how could I get them?
No, I have not compared these methods. I have studied the MLS method specifically and found that it is indeed sensitive to time-variance which leads to problems in large rooms and very large problems outdoors.
There have been some papers on the log sweep method, most notably by Müller & Passarini in JAES vol. 49, pp. 443-471 (2001).