The flashback is... unnecessary at this point, to say the least. If the timing was better then I would have probably been more interested (but seeing what kind of guy Oden is, I doubt it lol), but as of now I'm just rolling my eyes xD
Putting in a flashback that doesn't,,, add ANYTHING TO THE CURRENT SITUATION,,, it's just not good writing in my opinion xd
There were multiple opportunities to add in this flashback when the stakes weren't as high/we weren't left on a cliffhanger (most noteable the Prison-plot) but now...? I can't blame anyone who wants to get to the fighting, seeing how we barely had any good action for like.... pfff, 60 chapters xd? So yeah. I would also much rather just get to the war than dwell on Udon for another 10 chapters....