i would of thought the same as you...
we had to tighten it on saturday as on full lock the belt was squealing, so took it off to rule out a problem with the power steering pump. then it took a lot of fiddling about with a couple of raised voices to get the belt back on and that was with the lower idler wheel removed, (this was put back on at the end of the job).
my friend who is an experienced mechanic expressed his dislike for working on my car again! says its the worst that he has ever had to work on. and his initial reaction would of been that the belt was too short by about 20-30 mm.
its printed with: [6pk 1660]..
any way its on and tight now and no problems but thought i would check any way.
thanks.