See, I don't have problems with anything but sugar alcohols, which I have a SEVERE reaction to (I just tell people I'm allergic to them, because the reaction is so bad).
I think the article is wrong in saying "sugar is not an IBS trigger," because for some people it is. And while some people cannot tolerate any artifical sweetners, others can.
And the reason for this discrepency is that IBS is a catch-all term for anything wrong in your guts; there are many different things that might be wrong with you that could fall under the heading "IBS." So someone with a bacterial overgrowth may be made worse by consuming real sugar, while I (who have no gall bladder) am fine with sugar, Sweet N Low, Splenda, and Equal. As far as I know, I'm okay with fructose, although I have a problem with most fruits. I don't have a problem with sweet fruits like raisins, dates and figs, but I do have a problem with apples, pears, grapes, oranges, etc. There I think the problem is not the sugar but the acid. The fruits I can eat have little to no acid in them; the ones I can't have quite a bit of acid. This is also the reason why I have to be careful not to drink too much Kool-Aid, and why I can't have more than one non-caffeinented cola. But there are other people on here who have no problem with acidic drinks and food.
Everyone just has to test their own diets.