Although my cash and gold woked out better, I did kind of screw up my bear market fund (bearx) timing. I bought it in 2007, expecting a recession in 2008. The S&P500 gained about 10% after I bought the fund. Now it had to drop about 9% before I even broke even. That's as close as I could call the top.
The S&P500 then lost close to 20% and the media was acknowledging that consumer debt was too high, savings had to increase, and spending was obviouly going to drop. I held on, but the market rose about 10% after that. At that point everything I was expecting seemed to be out in the open, the market had pretty much hit bear territory, and had risen substantially to right about the point where I had bought the bear market fund. So I went ahead and sold the fund and went back to normal equity funds. There was one rebablance I was able to make between the buy and sell, so I did make something with that at least. I sold the gold (fsagx, not the metal) at the same time, but it was up 38% at time and then fell with the market, so that was good timing even if it was luck.
So two keys to timing: hit the peak and hit the bottom. Miss the peak and the bottom by just 10% and you could have a bear market and not make anything. I'm not sure I would bother trying that again, but starting retirement into an expected recession made it seem reasonable at the time.
I did better with my cash, though the primary reason I was taking out cash was to fund the first couple of years of retirement during the expected recession. My largest equity to cash conversion was within a few percent of the peak, the rest was again about 10% early. When the market went below 20% for good and DW decided she would continue working, I divided the cash (minus 2 years living costs) into 5 equal parts and invested one part each time the market hit another 5% down (from the peak). That took me to 45% from the peak (I skipped 40% since it happened so fast), at which time I added HELOC borrowed money for another 2 steps down to 55% using mostly ETF's. I was adding money 11/20/08 at the bottom (so far), so that ended up pretty well. I have used some of the reserved money to buy cheaper ETF shares during dips and sell the more expensive shares at peaks.
I have maintained my AA and rebalanced at my trigger points (+/-20% imbalance for any fund) during all this, other than having cash when I'm nominally 100% equities.
I always set a target point where I will buy or sell equities. It is impossible (for me) to know if any point is a peak or bottom. I just try to be within about 5%-10% of the bottom by buying all the way down. I don't want to wait until the market is 20% above the bottom and then jump in. There's still no guarantee it will continue up instead of going back down again. And you know the bottom will be when things look absolutely terrible.
As it is, I will have some shares I can sell at a gain even if the market just slowly rises out of this recession. Probably good enough to match my retirement projections at least, but hopefully better! If the market starts exceeding my retirement projections I'll be able to convert to cash again and be ready for any future dips (I hope). I will definitely continue doing that.
. More than one way to skin a cat. Heck I've known people who retired on rental RE and CD's. 
