I can't escape a Mint Julep comparison with this one. Cynar and Chartreuse lengthening the demerara and mint, respectively. This measure of lime doesn't seem to get in the way, but simply heightens the expression of ingredients a small bit.
This cocktail is one that has lots of things that I like in it, but when you first try it, it seems horribly out of balance. Even after a long stir over ice, and then serving it in a rocks glass over ice, it still needs some time to mellow out in the glass before everything comes into balance. At that point, it's a good - not great - cocktail. But all the same, an interesting one to try if only for it's eclectic composition.
I feel strongly that this adaptation is thrown way off balance by the addition of a 3/4 oz pour of lime juice.
The original was a long shot that became popular but broke the rules by adding a small(!) amount of lime to a stirred drink. I feel the original is much more balanced and works for a stirred drink with:
1oz white rum
1oz Cynar
1/4oz chartreuse(green)
3/4tsp rich demerara syrup
3/4tsp lime juice
That formula, I think, makes for a better, more balanced drink.