Blue loctite isn't that much burlier than just greasing something. The real point is you want something slathered in between the Al and the steel to prevent galvanic welding.

People seem to be going bananas tightening stuff lately, folks gotta realize that overtightening strips more stuff than undertightening. Do what people are suggesting here, put the cog on, ride, tighten lock ring well but not he-man tight, and ride. Perpetually tightening the crap out of stuff will eventually strip it, especially on a bike that is subject to a lot of temperature changes.