I think you might be a bit deep in your cups on Navy Grog - there's multiple typos in the description.
I'd say that's a bit more than "slightly" sweet.
I've had less sweet ice cream.
Added an ounce of 80 proof vodka to it based on your review - it helped cut the cloying of the original.
Just okay.
A nice summer drink.
Made with Elijah Craig Small Batch and Cinzano Rosso. Delicious double in a DOF glass with a large cube.