Nah, 'triangulation' is probably not the best analogy.
Let's try this:
Single GPS receiver is like walking a 2 inch wide plank while trying to place a full glass of water on a 3 inch diameter post in a room lit by a strobe light. The plank is the earth rotating, the glass of water is your MR, the 3 inch post is the location you desire, and the strobe light is the GPS satellites refreshing. Since every element of the equation is moving, 2 meter accuracy is pretty good.
RTK adds a base station receiver that is like adding a wall for you to brace your other hand against. The base station reconciles multiple fixes over time to establish a precise present location, and predict future location trends (on the rotating planet surface). Using this dead solid reference point and the kinetic measurements of the rover unit, RTK claims 2cm accuracy.
Since the base does not directly measure direction and signal strength of the rover, my triangulation analogy was missing a leg.
What else am I missing?