Bard's Guide To Combat Roleplay

In the second example, and one I make a point of demonstrating, very few people will ever have their character fall for a feint. I play a character that is a sword dancer, who relies on swiftness and trickery.
I notice this too. Unless the opponent is a very experienced swordmaster, even an elf that's over 100 years old and been at it for a long time, shouldn't always see through feints and stuff. People mess up sometimes. Experienced fencers irl that's been practicing for five or more years and seen lots of different moves be done on them, mess up. Maybe a bad day and the fencer's mind is on that occurrence rather than the spar, or simple clumsiness ruins good footing and it throws the duelist off.