Isner CAN'T destroy ANYONE! He can beat anyone or lose to anyone, but all of his matches are tight, even the straight sets ones. If some player gets trashed by Isner (like 6-2, 6-3, 6-1) the guy should retire.
This. Isner's got by far the worst RoS on the tour, I believe he wins just 11% of points when returning serve, which is god awful for a top 10 player. Isner "destroying" someone is 6-4 6-4 6-4 match - no tie breaks and 3 straight sets is the closest he ever comes to destroying any player, which isn't a surprise considering how awful his ground game is.