IIRC Magnus Carlsen is said to do something like this as well - he'll play opening lines that are known to be theoretically suboptimal to take his opponent out of prep, after which he can rely on his own prep/skills to give him better winning chances.
You can score points against e.g. national team members who've been 5-0'ing the rest of the pool by doing weird cheap tricks. You won't win though, because after one or two points they will adjust and then wreck you.
And on the flip side, if you're decently rated (B ~ A ish) and are used to just standard fencing, if you run into someone who's U ~ E and does something weird like literally not move their feet, it can take you a couple touches to readjust to someone who doesn't behave normally.
Unlike chess though, in fencing the unconventional stuff only works for a couple points. You can't stretch that into a victory, because after each point everything resets.
Maybe that's why pentathlon (single touch victory) fencing is so weird.
I can sort of confirm that. I never learned all the formal theoretical standard chess strategies except for the basic ones. So when playing against really good players, way above my level, I could win sometimes (or allmost) simply by making unconventional (dumb by normal strategy) moves in the beginning - resulting in a non standard game where I could apply pressure in a way the opponent was not prepared for (also they underestimated me after the initial dumb moves). For me, the unconventional game was just like a standard game, I had not routine - but for the experienced one, it was way more challenging. But then of course in the standard situations, to which allmost every chess game evolves to - they destroyed me, simply for experience and routine.