By "fully invested", I mean at 100% of your normal stock allocation. So if your default position is 60% stocks and 40% other investments I would call a 60% allocation to stocks to be fully invested.
For the record, I am mostly out of stocks and hedged to the downside, so I’m not cheerleading for everyone to get back into stocks.
Although I have substantial investments in fixed income instruments I have not owned any stock at all for five years. My equity has crawled ahead at tortoise speed, but unlike stocks, it has always moved forward.
The only thing that would draw me in is information about a particular stock that corresponds with my personal knowledge. That was the case with the last stock I owned and resulted in more than doubling my money.