It really depends why you're arguing for it's use. Aside from illiciting a large insulin spike, which can be beneficial for maximum protein synthesis, it doesn't really serve any purpose. One of the main reasons proponents of its use always provide is that it "quickly restores glycogen stores". However, they never mention the relevance of this, which is really quite low. Unless you are planning on doing another workout a few hours after you just finished one, who cares? It's not like you won't be eating carb-containing meals before your next session. Your glycogen stores will get replenished eventually, timing is of little importance.
And speaking of timing issues, if you are really that concerned with this quick glycogen replenishment, remember dextrose still takes time to be digested. It's what you eat BEFORE the workout that's going to be getting put to use directly after the workout.
So, at this point it seems as though you may as well take it; it's not harming you and it might help with protein synthesis. This is where you have to remember dextrose is just SUGAR...think long term, this can't be a healthy practice.
Before I get jumped all over, let me say this: One can use dextrose if one wants, it's just not necessary, and I really disagree with people preaching that it is.