Even within WVR, you can NOT obtain a lock on the jet...the radar signals are still looking for the actual location as the wavelengths are scrambled going back to the -16. But the pilot is seeing the -35 in front of him. The only way to get a lock is to use the IR. The guns don't use IR. So the lock is obtained during simulated combat. I wouldn't read too much into these tests as they mean nothing.
These were simple tests, beyond the scope of the -35's flight envelop. Current technology doesn't use guns with IR locks. Guns are radar guided in today's aircraft. The main issue with these tests that got over hyped through the media wasn't that the -16 locked on a -35, it was the fact that the maneuverability of the -35 wasn't exactly matching the -16 its replacing. And its not suppose to either.
But the media hyped it, without knowing that the -35 is NOT a dog fight plane. In fact, I'd be very surprised if 1% of the -35's ever get into a WVR fight even with AIM 9X's. The purpose behind the -22 and the -35 is to form two tiers of stealth and advanced electronics to monitor, control, dominate, and jam the airspace to establish air supremacy; as and when needed.
Once major enemy air assets are taken out, like air defense systems, major air fields, primary defensive top tier fighters, you'll then see -16's, -15's and -18's doing the remainder of the work. And those guys still might see 10-20% of WVR / some dog fighting action.