This is hard to believe, unless you had insufficient coolant or it had turned to molasses. Are you sure you didn't have a leak somewhere? Some hose connections are known to leak a drop here and there.I just Changed my Coolant to Engine Ice on My 2004 RC51 on Saturday. I drove the bike to work today and it it running about 30 degrees cooler than before. a huge noticeable difference.
The coolant acts a as surfactant, and allows more water molecules to contact the metal surface of the radiator to transfer heat.
Similar method to washing clothes. The surfactant (soap) breaks down the water's surface tension and allow the water to fit through smaller spaces than water itself could.
The water lifts the soil off the clothes and is held in suspension by the detergent.