Он говорит, как бы он умнейший ученный в мире. is incorrect. Only как будто means as if.
Как бы means "kind of, sort of". It's not a very good phrase to use in your speech because it's now usually percieved as a filler. But it's widely used in collquial speech though
iCake ya ponyal. No ya nashel vyrazhenie: "Благодаря этому, ..." v moei knige universitita i ya prishel k vyvodu chto eto ochen' vazhnoe vyrazhenie.