Timzsta, you're chasing a red herring about the wake vortex issue. What is the alternative- to take out every airport that has a heavy jet movement for 10 minutes until it has completely dissipated? Wake vortexes are something we have learnt to live with acceptably- it was not the wake vortex that caused the crash, it was just a link in a chain like an aeroplane crashing on a fog approach- it's not the fog that is the cause, rather the procedures and handling of the situation. All jet pilots fly through wake vortexes, it is unavoidable. One just has to ensure that the short duration encounter is handled.
Before proper separation standards were imposed, we got caught once flying up the core of one very close to where AA crashed. On a Canarsie approach into JFK just after Canarsie onto R/W 31- slow and low. I was handling and it took almost full aileron on a VC10 to attempt to keep level. Once 'stabilised', it then took an interesting few seconds to exit it! An immensely powerful phenomenon- I have no doubt something smaller would have ended up upside down. But the separation standards we have now are adequate- it's other things that must be examined.