Indeed. The real world performance of Patriot PAC-2, the first generation tweaked for BMD but using the same hardware except for increasing the size of the warhead's projectiles, says little about how later versions and generations (PAC-3 uses a dedicated missile, 1/4 the size and therefore 4 times as many in a launcher) also preformed in the real world.

Since in this case the real world = actual instances of enemies shooting live missiles at you trying to kill you, it's been proven in some acid tests. And one reason Guam is sprouting Patriot and THAAD batteries.