I've come across a number of pilots who claim that during a late flare from the F/O and in order to save a potentially hard or firm landing, pump the side-stick at short intervals in a way that the dual input doesn't sound.
I think this thought originated from incomplete understanding of the system. First thing, even a small movement out of neutral will give a command to change the pitch and depending on what the other stick is doing it will impart the LF or AoA as demanded if other stick is neutral, added if the other stick is moved in same direction or subtracted if other stick is moved in opposite direction. Dual input will sound when the sticks are moved beyond 2°. Once on two consecutive Landings the FO didn't flare at all so I flared at 10ft. and let go. He was happy with the result. I told him you didn't flare I had to flare. He said but there was no " Dual input". I said that's right there was no dual input but the single input was mine. I should have taken priority. The practice of fiddling with stick is senseless will give confusing results. The correct practice ask him to flare or press TO button and do it yourself. There's no follow me on controls in Airbus.