A Tom Pope brace helped in-form Port Vale crush Sky Bet League Two leaders Luton 4-0 at Vale Park.The home side were up at half-time through Dan Potts' own goal, before Pope's strikes sandwiched a Ben Whitfield tap-in to complete the rout.The deadlock was broken after 23 minutes when Whitfield charged into the box before his cutback rebounded off Potts' legs into the goal.Vale doubled their lead on the hour when Whitfield broke quickly and chipped a pass to Pope, who brought the ball down perfectly to slot past Marek Stech.Pope turned provider 10 minutes later, winning the ball in a dangerous position before squaring to Whitfield for a simple tap-in.The hosts scored their final goal eight minutes from time when David Worrall chased down the ball and crossed for Pope to stab in following a goalmouth scramble.The veteran striker could have had a hat-trick but his 42nd-minute header went wide after he was picked out by Cristian Montano.