Interesting - time to blow the dust off my Nutribullet perhaps!

I get a security notice from that link.

Personally, I do not think blitzing fruit is a wise choice as it destroys the fibre and the liquid gets to the liver far, far faster than whole fruit does. I havn't tested but I reckon if I tried a fruit smoothie I would see a fast, sharp rise in bg that would take longer than usual to come down.
Lowering the GI/GL does not mean that the fructose will not be absorped just that it may take longer to be absorped.

P.S.

Another way to look at it is the amount of fruit it takes to make a juice/smoothie. My lad puts 4-6 apples into one smoothie, I asked him when was the last time you had 4 whole apples in one sitting? Same goes for other fruit.

Does the Nutribullet remove fibre from the smoothie? I know some machines do, and taking away / over-blending the fibre could cause trouble for some as Guzzler says. I'm tempted to replace my coffe grinder with a Nutribullet as its supposed to make excellent flour from low carb seeds such as flax, but then I would just be using it as glorified mill and its probably a bit expensive for that. I can also be a bit Scroogie when it comes to replacing things that have not worn out, so I could be wating a while. Mind you my low carb bread manufacture / consumption is increasing rapidly, and the poor coffee grinder may not be able to cope!

We now use the nutribullet for making ground almonds, almond flour and nut butters but only if we need small amounts. Larger amounts go into the food processor.

Back in my Green Smoothie Phase (oh, those were happy days...) I was always delighted at how small a blood glucose rise I got from the smoothies. I use(d) a Vitamix, so it was whole fruit/veg, blitzed to a velvet smoothness, rather than extracted juice, or roughly mashed fruit. And I used yoghurt or water as the liquid instead of some sickly processed fruit juice. And sometimes I added psyllium husks to give a gloupier texture, more fibre and slower carb release.

The thing about green smoothies (which are a combination of fruit and veg), is to get the flavour of the fruit and the benefits of the veg, and you get to design your own smoothie. The often quoted figure for a good balance is 60% veg, and 40% fruit, but of course you can tweak that to your heart's content. Less fruit, or less sweet fruit, more mild tasting veg (like courgettes) = less sugar. Even blitzed fibre does a good job at slowing bg spikes. Maybe because the soluble fibre is already in solution and doing its job?

And if you add nuts like cashew or macadamia, and count avocado in your fruit %s, you can increase the healthy fat content while simultaneously slowing the digestion and the speed that carbs hit the bloodstream.

There is a lot tweaking that can be done, to make sure that the smoothie doesn't hit the bloodstream like an express train.