Yeah, i have. If you are holding him up as the paradigm of great footwork, you haven't. Clearly, this fact isn't going to sit well with your fanboyism/inability to admit you made a mistake (whichever it may be) but it is a stone-cold concrete fact that Whitaker does not have the greatest footwork of all time.
Lomachenko has really impressive footwork. Pac has extremely quick feet but not technically all that great
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Kovlaev has excellent footwork. So does GGG. Danny Garcia has very good foot work , if you know what you're looking at.
Arguello had good feet (nothing fancy but even backing up he would plant/turn his backfoot and deliver a straight right down the middle with power).
Rigondeaux Cross's his feet, so does Sweet Pea & Lopez and I'm sure many others, but these are just a few I've noticed that are often seen as having elite footwork. However I think that the difference is all these fighters did it at a range that they were not able to be hit, they were not crossing their feet when on the attack or defence.. It was often slightly out of range while trying to manoeuvre their opponent into a good position.