Intruder and Duet

[Shah90]

Why am I seeing so many people calling the two episodes Intruder and Duet 'Fillers'?

Granted: They don't add up too much to the general Arc of the Story but they gave us a lot of important information...as to what happens to the people that get beamed up into a dart, how to take them out, the fact that Wraith ships can give you viruses and what not?...I can go on forever...plus they can't use their beaming technology against the Wraith..or can they?

[Deputy-Assistant-Second-Prime]

Many shows do this...introduce concepts or explore ideas in self-contained stories that wind up being very important, even vital, to the goals of the characters.

For example, when SG-1 met the people of Orban, they were taught how to build naquadah reactors. We never saw Orban again, nor met the Goa'uld that once enslaved their world, but that technology became vital to their future endeavors.

So people forget about this episode and post questions like...
How did Carter figure out the naquadah technology?
Which SG team discovered this technology?
Why don't they tell us how they acquired this technology?
Because the writers cunningly slip this information in as trivia or as a story device. If they made such a big deal about it, it'd be like posting spoilers for future stories.