Do larger than average eye floaters eventually fade or break up into smaller pieces?

Several possibilitie: Usually the "floater" is assimilated into background "white vision" by the brain and not noticed even though it is still present. Less common is the dissolving of the floater. Rarely gravity can pull it down away from the visual axis.

Sometimes: Floaters are a consequence of protein particles drifting within the vitreous fluid of our eye. They are common and harmless most of the time. Some may settle and no longer be visible. Some treatment options are available for large floaters that obstruct vision. If they are new, or associated with other symptoms like flashes, the eye should be examined for retinal problems.