Comments on Act III, scene vi
In the Ian McKellan / Trevor Nunn production (RSC 2009), after Kent has taken Lear toward Dover, Cornwall's men arrest Gloucester at gunpoint, and hang the Fool, as he recites a speech from an earlier scene. This added stage action helps explain the Fool's absence in the rest of the play.
In a 1982 RSC production, Lear killed the Fool (Anthony Sher) accidentally in an insane rage, thinking he was dissecting Regan's heart.
In the 1962 RSC production, Alec McGowen's Fool seemed jealous of Lear's attention to Poor Tom, becoming more angry and distant as Lear ignored him.