so what is really happening is that the ''proofs'' are not sufficient. only a study had be done by the Philippine department of agriculture that is showing that the GI is 35 while i think the average of table sugar is 60 but the department didn't compare it with the table sugar but with glucose :P Also the GI of every human being is different so even 35 can be a lot. Different as well can be the product of coconut sugar and the way they made it so again the GI can be a lot higher.
Finally in america in terms of people that face diabetes they don't even bother with the GI and according to the American Diabetes Association in the process of making the coconut sugar they sometimes add fructose etc etc increasing the GI :)
basically the differences are mostly none. as i said in terms of taste it is really good but if you wanna replace sugar with it, that's not the best option. i hope i helped you!
Thanks!