I have also heard that GM Oscar Panno said that -whenever you have to make a rook move and both rooks are available for said move- you should evaluate which rook to move and, once you have made up your mind. . . MOVE THE OTHER ONE!!!
In a rook and pawn ending, the rook must be used aggressively. It must either attack enemy pawns, or give active support to the advance of one of its own pawns to the queening square.
The Bishop and Knight, in contradistinction to the Queen and Rook, are called Minor Pieces.
The only good Rook is a working Rook!
Always put the rook behind the pawn. . . . Except when it is incorrect to do so.