When Robin and Friar Tuck are in Sherwood on the banks of the river (Robin is eating the mutton joint) the bottom of the Friar's robe is dry. When Robin throws the mutton joint to his men in the bushes he jumps onto the Friar's back. When this happens the bottom of the Friar's robe is now wet! This must be a second shot/filming of this scene (wading into the river), and the producers have forgotten to give the Friar a dry robe.