Yeah. Yes. I do believe "offhandedly" works. I'm used to "offhand" being used in a very anti-me sense, however - as in dismissing logical arguments offhand - so I'm a little reluctant to use it. As far as M-W goes, though, the word fits.

I saw that sentence and was wondering if that was a correct use or not; on third glance, however, I think I know a way to avoid the question entirely. I'll deal with it. - ZM