And the optimized party is mysteriously barred from using the very same good tactics because...?
This means nothing, since all other things equal, assuming both parties are using similar tactics, the optimized party should always come out ahead.
You might try looking at the post I was responding to, but one thing 4E did was put more emphasis on team tactics rather than individual prowess. Leaders, controllers and defenders add a whole lot to a party when played well and allow for better rounded characters and "flavor spending". One of my main attractions to 4E was the superior 'team concept' rather than powergaming my character in to godhood without regard for any other character.
I also see many who appear to think optimization IS good tactics, which is kind of silly. The even more dynamic battlefield is a wonderful addition to the game and allows a lot more flexiility in character building.