The term "groove metal" is one of those labels that get thrown around at times.  You sometimes hear that when discussing groups like White Zombie or Pantera.  Of course, whether or not the music in question is actually "groovy" is largely subjective.

That is not a term I would generally use to describe the music of Megadeth.  One glaring exception, however, is the opening track from Youthanasia (1994), called "Reckoning Day."  I'd say this tune is pretty damned groovy.

Yes, sometimes speed metal groups made some amazing stuff when they weren't being speedy.

Watch the video for "Reckoning Day" on YouTube.  Would someone please tell me what's "explicit" about this?  Maybe I'm just blind and stupid, but I'm not seeing it.