I'm too lazy to search for the thread, but ~4 months ago there was a similar thread.
I made a backtest and posted the result.
The result was, that such a strategy might be profitable in bull markets, but not better than buy and hold.
And in bear markets your are loosing very much.
I completely disagree with the second part of your statement about bear market, let me elaborate why. Lets assume that three consecutive days a value of BTC is falling against $, each day 2%.
The guy 1 with buy and hold strategy would realize 6% loss.
The guy 2 with would realize smaller than 6% loss because of holding fiat when market price is bellow the 100SMA and 100SMA is bellow 200SMA. That could result in BTC sell off when it was lets say 4400$ and buyback at price 4136$ or -6% (-264$). So this guy would able to buyback 1.06BTC in ideal scenario.
BEAR MARKET - downtrend BTC/USD
Guy1 result