Hi Rhino,
I'm posting some pictures of me wearing my weathered TD armor, to give You an idea of "big blotch" pattern.
Consider that I'm NOT a S.W.A.T. officier, and that my weathering is not the best one in the world... so it is not something to aim for, but it is still "passable".
As Deadvision told, I used big blotch of paint on the chest and other armor parts. I like this approach because the weathering is still visible under direct sunlight.
Even if it seems not so weathered, when indoor a lot more of weathering appears.
Cheers,
Alberto