I agree about Hagler!.
About the aggressive lefty vs pressuring lefty, are you saying that Winky is (was) an aggressive lefty and Williams/Calzaghe are pressure lefty? Am I right?
Anyway, let's pick up Williams and Calzaghe 4 example. They are similar fighters: speed, stamina, rythm, very good chin, love to pressure. But I'd fight them in two different ways: Williams showed us that going straight into his punches is useless, I think that against the guy I would act like Martinez/Quintana, probably being elusive is the key.
Being elusive/counterpunching with Calzaghe is useless, if Hopkins wasn't completely able to do it, I don't think anyone on the earth is. Against Joe I'd try to pressure him (I'm not so sure that this could work because Williams showed us his problems, Calzaghe didn't that much) in a better way that Lacy did.
What I' trying to say is that I generally think that putting pressure against a southpaw is useful, but not always.
You know just thinking about what you said about aggressive Southpaw's and yeah i think your right to a degree, i mean i always thought the best way to fight Marvin Hagler was to pressure him and throw lots of punches at him, so yeah i can see that what your saying, particularly as i advocated that orthodox fighter can have success against a lefty if they put pressure on them, i guess its the same vice versa, i guess what i did not make clear is the difference between an aggressive lefty and a pressure fighting lefty, an aggressive lefty might not press you as hard and throw as many shots, where by the pressuring lefty is not going to leave you any spots to counter because of the amount he is throwing at you.