Yes, the MOT history is really helpful. If there was serious rust noted in, say, 2012 but not 2013, was it properly repaired with panels cut out and new metal welded in? Or was it just covered in underseal or patched over? You can go to look at a car forewarned for close investigation.
Another car that I researched had serious rust leading to an MOT fail in 2010 and then passed without any rust advisories the following day! Interestingly it failed again for serious structural rust in the same location the following year, was then fine again a few days later for the re-test and failed yet again for the same thing the next year!
Needless to say, I didn't even bother picking the phone up to enquire about that one! If you see anything like this in the history, save yourself the time and move on, unless you are looking for a car to restore and it is cheap enough to make it viable.
Edited by Lordcroker, 12 July 2016 - 11:53 AM.