A narrow front sight should/will be a more accurate sight than the lump of a bayonette lug.
How accurate it and/or how consistent it might be, depends on you and the gun, the load, the wadding or patch and it's fit with the ball of choice along with how much you practice with it. Within reasonable ranges, guys who shoot nothing but smoothbores, are more accurate with them, then people who shoot rifles but do not shoot nor practice very much with them.
I have to keep reminding myself of the silhouette match a the Hefely Creek Rendezvous some years back - 2008, I think, the highest rifle score was lower than the 2 highest smoothbores scores - on the same targets at the same ranges. The smoothbores had difficulty with the 100yard targets (so did the rifle shooters), but those shooting smoothies didn't miss with targets out to 50-60 yards nailing every one of those, whereas most rifle shooters had difficulty at close ranges as well.
The person who practices, will have more 'hitting accidents' than one who does not practice.