Absolutely, unless you want to get thoroughly confused.
It can be done, and nothing’s going to “break”, but it’ll be a pain in the ass to try to switch modes.
Eg, what you’d normally do with one half-press when on, you’d have to turn off the light, wait long enough, half-press it long enough to simulate it being “on”, then momentarily release the switch and quickly half-press it on again. Or release-then-press multiple times to simulate multiple half-presses of a RC switch, then full-press to keep it once you get to the mode you want.
Like I said, it won’t break anything, but it’ll be damned cumbersome.
FC lights like it best when you just keep it on one usual mode (eg, moonlight for not blinding yourself at night, or 100% if you want it at its brightest), and optionally just half-press initially to get to a different mode if you want.
That’s why, to me, my favorite lights are FC 1-mode lights (eg, my F13, L2M, etc.) that are full-tilt all the time, and I don’t have to worry about changing modes. Should do up a few C8s that way…
My WK50 is an exception, as I normally keep that on moonlight, know it’s on moonlight when I’d flick it on once, so if I want anything different, I half-press as needed to get to the mode I want. Then when I’m done, go through the process again to put it back on moonlight.