Nice chart and interesting thinking ...

Note their view of the curve going forward and their thinking on the S&P correlation to rates.

There seems to be some logic in this - as growth accelerates to trend and beyond rates "mean revert" during this phases stocks generally benefit - the problems come when/if the Fed starts to tightening to restrict excess investment/capex (sometimes speculative) that leads to over-capacity - then the market sells off because it takes the Feds actions as a clear signal that too much capacity is getting created and that prices, earnings and profits cannot be sustained ...