bottleneck movie

having seen the other 3 main movies and having seen bits of this over the years, I finally watched it all the way through last night.
With such a limited cast, situations that are only explained through deleted scenes, bad exposition lines (like Kevin's "law school" comment, which I guess even the writers pretended hadn't happened because he's an architect or something in the 4th one), and the fact that it looks like it was all filmed on about 3 settings (the wedding venue, some bar and Jim's house which didn't even look like Jim's house from the first 2 films) it has the feel of a low budget filler film - kind of a bottleneck episode like I said in the title. Which would be fine for an episode of a TV series, not so much for a 100 minute film that people are paying to see in its own right.
The whole thing, including the editing at times, seems rushed, and I wonder why. Were they under contract to get the 2nd and 3rd films out within a set deadline? Or did they feel they had to get it out in the summer of 2003 while the 2nd one was still fairly fresh, like 2004 might have been too late and they'd have lost momentum? Maybe they wanted to leave no more than 2 years between each film.
Surely it was better to wait and have Oz, Heather (maybe as a double wedding?!), and maybe Vicky and her friend and Sherman and Nadia involved too? Hell, the milf guys are ushers and Jim barely knows them!
Overall, I can't help feeling that this film was 2 or 3 years too early and then the reunion was 2 or 3 years too late.