Charl,
I think that indeed short term algorithms are mostly driving large players programs during the summer because they hedge their longer term positions. Programs using longer term floor levels are usually back around Labor Day. Hence LT floor confluences prove to be less powerful now as potential support or resistance than during the rest of the year.
Your observation about anchored VWAP from March 2009 is very judicious. But the current reading is closer to YS1 (64.40) than to MS3, QS3, SS3.
Billy