I think it probably happens more than we know, but is handled quietly and as a "transfer".
I mean, I know it's going to stir up a hornet's nest of Nesta Bros, but Mario basically told Silvera to leave. The headline was never that he was "cut", and the Nesta Crew bitterly complained about the accurate characterization of the circumstances. But it happened.
The point is, if a player KNOWS that a coach can cut him, he might as well put the best possible face on it and call it a "transfer". A lot of the Gaytor fans are concerned that Gaypier let it get out into the press that these players were "cut", and it makes him and UiF look bad.