Pietro, if the video is on the internet, perhaps you could provide a link. There are so many variables, that answering your question is difficult otherwise.
Normally, closing the thrust levers in 50 feet would not be a good idea, nor inline with Boeing recommendations (no difference for SFP equipped aircraft).
However, external circumstances may make it necessary to deviate from normal practice. Example of such could be changes in wind, which causes the indicated airspeed to rise, and may make it feasible to retard the thrust levers earlier than usual. Likewise, it may be necessary to add thrust during the flare in some circumstances.
The procedures are written for a "standard day". The atmosphere is not always aware what is written in our books. And, yes, this is where "feel", training and experience comes in to play. And, yes, along with the procedures, "feel" is used on every landing.
