@NikTamMy comment had nothing to do with bull market or bear market, it was purely based on risk vs reward. When I followed your CML backtest links, I see trade iterations collecting credits of 1.00 on spreads of width 7.00 - so risking $6.00 to make $1.00. Or collecting credits of 1.50 on spreads of width 10.00 - so risking $8.50 to make $1.50. So the risk vs reward is somewhere between 5:1 and 6:1 (I'm not sure where you are getting the 2:1 that you mentioned). Multiple things can cause big gaps down in stock price, overall market big downturn, analyst downgrade, etc - and a big gap down will cause you to lose a lot more than the credit you collected. My point is that you cannot look simply a win-loss percentages on these low delta credit spreads trades because one significant loser can wipeout gains of many winning trades.
Regarding the 1-2 day profitable trades - these are great if they perform as planned and we certainly have been in a long term bull market that should help them. For myself personally, I try to avoid being too delta positive on my options trades - with a lot of money in 401k being long the market, I don't want my options trading account to be more of the same. I want to be non-directional with options trades and give them a chance to make money in both up and down markets, knowing that they can make money when other long market accounts decline. This is not a knock against making these directional trades, its just my preference to stay non-directional with my options trades (and I think many people were drawn to Steady Options because of the non-directional aspect).