It's not that uncommon.  Especially now that a lot of 401(k) plans will allow you to roll IRA money into them.  Maybe it depends on your client base.  I think Google HR must teach a class on this stuff, a lot of my Googlers do this in addition to in-plan conversions from after-tax contributions to Roth.  It's a pretty big loophole for folks who know how to use it.