I'd like to state a few thoughts here (since I'm not in CDF anymore, you won't have to endure my long diatribes in there anymore
):
1. As far as I can see, trench had nothing to do with the length of the tournament. Certainly none of TOFU's wars have had the duration dictated by trench settings (neither of the two games that are likely to determine the current war are trench).
2. Most of the wars were exchanged in two batches, and the ones that weren't did not have the duration dictated by the third batch. In TOFU's current war, all of the remaining games were exchanged in the first or second batch anyway. The third batch games are entirely completed.
3. When it comes down to it, when you have closely matched highly competitive clans, wars can take a while to fully decide. You see that in the schedule. The first round started by the end of January. The second round wars all started by early April (~2 weeks behind planned schedule). Third round wars were started by mid June (a month behind plan), and semi-final wars started in September (2 months behind plan). Right now we're looking at a December start for the finals (still 2 months behind schedule).
4. Possibly the start of the two semi-final wars could have been expedited somewhat, but I think the only way to guarantee completion within a calendar year is to limit the competition to 4 rounds (16 clans). Perhaps the way to continue to allow more clans to participate is to hold qualifier wars starting in October of the prior year. A possible concept: You could have an automatic bid to the 4 clans reaching the semi-finals of the previous year, then any other clan ranked in the top 12 can have an automatic spot. The remaining 4 spots would be filled via qualifier wars.