Also not true. The text made note that while Skywalker couldn't see Palpatine with his eyes, he could follow him through the Force, which is how powerful Force-sensitives fight anyway. Windu himself only saw Palpatine as a "blur" during the fight, but still managed to best him anyway, further rendering your point useless.
Seeing someone as a blur is a higher level of perception then perceiving someone to be moving in and out of existence. While I'm sure Anakin could react against a few strikes from Sidious similar to Fisto he'd be overwhelmed in short order.
Also Sidious allowed Mace to best him making your point invalid.