I've seen comparisons that make Kennen look pretty appealing as an AD carry.
-Kennen W at max rank deals +80% AD every 5 attacks (in magic damage) while Caitlyn's headshot for example deals +50% every 6 at max level.
-Supposedly Kennen's Q serves as an autoattack reset for some reason, which no other AD carry besides Sivir has.
-Better escape than any other carry besides perhaps Tristana
-Better base attack speed than every carry (tied with teemo if you count him). Keep in mind that AS increases are percents of the base, so differences in base AS end up being multiplicative. Also good natural AS per level.
-And, of course, stuns all over the place.
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