Interesting closing

The last 20 minutes of the market were on a tear...

Here we are, I've noticed this occurring with more frequency late during the close of Fridays. However what was even more interesting is the chart below.

What was more interesting is the corresponding move in High Yield Credit which nosedived, the last minute of the day it completely decoupled and made the biggest 1 min. move of the day, almost the biggest move of the day period.

So if Credit leads equities, I wonder if a end of day plunge like this should be any more thought then an odd curiosity?