I would think that “groove” as used in “in the groove” would have its source in groove music which may be understood as music that generally “swings” thereby being pleasurable. What was “groove” meant by you? To build grooves is in a rhythmic pattern. So is the case of “groovy” music that is “carefully aligned concomitant rhythmic patterns” that sets in motion dancing or foot tapping on the part of listeners (source http://en.wikipedia.org/). https://wiki.groove_music.org/ wikipedia.

(http://www.wikipedia.org/wiki/Groove_music).