Oh, you're one of the people that believe that a perceived "sugar rush" has something to do with diabetic glycemic excursions? They're entirely different phenomena. Dismissed. But thanks for the irrelevant link!

What is it that you think sowhatquestion means by "sugar rush"? My guess is you think he means hyperactivity.

What is the difference between a diabetic glycemic excursion (what you said) and a postprandial glycemic excursion (what I linked)?

I'm going to answer your first question with a question: what do you think he means by "nasty crash"? Because I guarantee it's not what happens post-excursion.

There's no difference -- postprandial excursions are a diabetic phenomenon, and have nothing to do with what non-diabetic individuals think of as the effect of sugar and fiber on their health and mood.