I should have said that current conditions are making me very likely to follow some type of re-allocation strategy (if more market action starts to truly perform poorly, such as the 99 day high rule being violated, etc.) as opposed to a buy-and-hold.

Okay. Here are some more thoughts:

"The historical evidence is clear that the winning strategy in both stocks and bonds is to ignore all forecasts and stick to a well-developed plan." -- Larry Swedroe

One on point for the last part of your sentence:
"Being forced to sell at a loss isn't necessarily bad. There are plenty of Japanese and European investors that would love a second chance to sell at a 30% loss. You either have a plan or you don't. You either have discipline or you don't. Expecting all investments to just somehow work out by the virtue of patience is incompatible with reality."

That kinda says that you NEED to have a plan for dealing with bear markets. Or not. Statistically, timing improves the short-term swings but not the long-term returns, vs. buy-and-hold.

From experience I know that it is much easier emotionally if you have a sound plan that you have confidence in and KNOW that you will follow no matter what your emotions say.

There are a lot of potential plans, such as 99 day high, NH/NL, etc. The problem with looking at a number of plans is that you don't have a plan, you have a handful of sorta, kinda, pick-and-choose plans. That are never in 100% agreement, so you decide on the fly which to listen to and which to ignore.

I am partial to Growth Trend Timing. A 50+ page paper, but it's easy to do on your own (don't lean on others to run your timing signals, do it yourself). I backtested it with actual historical data and am satisfied.
philosophicaleconomics.com: Growth and Trend: A Simple, Powerful Technique for Timing the Stock Market