I agree with you.. one additional factor which increased the CRS was introduction of additional points for language and siblings.. Just to add..In 2016, nobody expected cut off to go below 450, but it went. In June 2017, nobody expected to be stuck in the pool with CRS 432 for more than 6 months, but it happened. So CIC being uncertain has always made it tough to predict what would happen in future.
But, yes if CIC continues issuing 2750 ITAs with 2 week gap draws, then the cut off won't go below 420.
Only hope for lower CRS folks is more number of ITAs OR 1 week gap draws!