It's not a bad thing to show what happens during that timeframe, it's just a really bad idea to do it in a tv show. Now if it were a book series that'd be different. But every single SW tv show has been awful. Every single one of them. But for some reason no one seems to care and just keeps hoping the next one will be good when we already know it will be bad.
I agree with you that every single show to date has sucked, but I also think it's a new era for Sci Fi on television. Battle Star Galactica and to a lesser extent Star Gate have demonstrated that with commitment and focus, you can do serious and even dark Sci Fi and not have it turn out like the dreaded Christmas special. I think it's partly technology in film making and special effects, but also partly a different way at looking at the plot and pacing of a TV show in the writing, with the long and short arcs, and non linear forms of story.
I'm an idealist: I hope the series will be totally amazing. And I think the time between 3 and 4 is very interesting: very wild west -esque.
Yes, I'm sure I'm setting myself up, but I'm old, and going a bit daft, it would seem.