Yes... thank you. i have thought about this. but... the reason why I did not test it through the bear markets is three fold:
1) first, i expect the immediate future to be more bull than bear, so bull market testing is more appropriate for the present (i think). i assume no interest rate hikes until end 2022 (perhaps middle 2023). (manual trader talking)
2) in the case of both bear markets GFC (2007-2009) and Covid (2020) i could see miles off to get out of the market ahead of time. both crashes were amply advertised ahead of time for anyone that actually paid attention. (I went to cash Dec 2007 and again January 2020). So, excepting an event like 1987 or 2001 (9/11), in which case there isn't a whole lot anyone can do except pull the plug, i am not too worried about a bear market performance. i assume i will just go to cash. yes?
3) because the routine uses a kind of price discovery gizmo, it can't really be back tested. all that can be backtested are the general conditions under which as stock should be given to my routine to trade. its the actual trading which gives me the clue -- in this case, September hiccup looks very good relative to market in general. but I will backtest the starting conditions like you suggest going back to 1998. i will take out the periods when I was in cash -- if I knew it then, I would not have been trading then, yes? bad thinking on my part?