Personally, no, but it can work and I have friends that do. There is a small benefit to it, and personally I'd rather use attack abilities, but it is definitely possible to do and there's definitely a gain in dps if you can pull it off. Whether it is worth the button spam is up to you.
And going off what Drasca said:
Example: Silent Sister. If you are having a hard time staying alive, guard going away fast. Attack cancel so you only hit with the main hand dagger. When your abilities are on cool down (mostly for before you get flow of battle) do the auto attack cancel to hit faster and increase DPS. Your guard will generate a little faster and you will kill faster so she can potentially stay alive easier, I do it when bringing her into NM before getting Flow of Battle and it help immensely.