Some time ago I posted on constructed attributes. There was a snafu in an item I posted (and by snafu I mean mistake).
I said that constructed attributes are only returned in base searches. This is incorrect in the general case. This is true for some constructed attributes (like tokenGroups) but not true for many others, including the example I posted! I should have at least tested to be sure my statement was correct for my example. Hindsight is always 20:20 I guess. 🙂
I hate wrong info, sorry to have passed it along.