i (mostly) consider myself an independent as well. it's not that all independents are less-informed, but that a larger subset of independents are.
of course, it's more complex than that very simple model that kat kid and i outlined (for example, better educated individuals tend to be more ideological, presumably because they are more aware and/or less tolerant of inconsistencies among their political opinions), but that explanation is sufficient to explain a good chunk of it