You do realise you based a lot of your arguments based on 'i don't see it happening', 'I doubt it' and 'not feeling it'. Not really strong argumentative points when you are trying to say what might happen in the future.
Well look at what's happening in the first episode, Ash vs Shooti, and it'll be a 1 vs 1. Unlike Paul who actually started out against Ash with Chimchar developing an even greater story right then and there. The reason it doesn't feel like there can be one now, is I don't buy the possibility that a story can be created later.
Are you implying that whatever pokemn story there might be this time with BW it can not be similar to chimchar story, or are you saying that there can not be a story only focused on a single pokemon in Ash's team? I thought you were saying the latter.
A little of both, but I'll explain in a minute.
The fact that Ash is getting a water starter after a long time and that the fans are excited about it could be a potential for the writers to make a great story for it. In that case the focus could very well be a little more weighted upon miju. I am not gonna argue how the story might pan out - there are way too many possibilities. Miju having trouble with its power once it evolves, being too cocky to listen to Ash, a bit too carefree to battle properly, or it might even develop rivalry with Shooti's tsutaja later in the arc.
The problem here is there wouldn't need for Mijumaru's hypothetical story to undermine the rest of Ash's team. The only reason Chimchar/Infernape did was because Infernape needed to show how strong it became while under Ash's command. But if it didn't have the story behind it, I doubt the same could be said about needing to be so strong. Torterra in that case could've easily beaten Electivire and previously Gliscor could've beaten Candice's Snover.
Now take your hypothetical Mijumaru and compare it to Mamoswine who had a very similar storyline. It might've gotten focus during that time, but it didn't hog everyone's screen time. Dawn still managed to properly show her other Pokemon in the process (and it wasn't until Lyra guest starred that Mamoswine actually got to be in a Pokemon contest).
Given that both Shooti and Ash catch a tsu each, there is potential to see which one is better. Shooti's one could be relying on raw power while Ash's one a bit more relying on evasive tactics and strategies. In that case Ash would have to learn how to handle his Tsu and that could make a nice story on itself, hogging focus in the process. They did not give us a terra vs terra in the sinnoh final, probably because Paul's terra obviously had the upperhand
with more training. But that will not be an issue with the two tsu, because they both will be newly caught.
There's not just the Torterra's. Remember both Ash and Paul have Gliscor, and any chance of it possibly becoming a which one is better trained went out the window (apparently Chimchar/Infernape was enough for their rivalry that they didn't want a Gliscor vs Gliscor since it likely would've undermined the importance of Chimchar/Infernape's story. It would be interesting yes, but again I can't see why this hypothetical situation would make Tsutarja get more screen time, given the fact Tsutarja isn't all of Shooti it really is 1/6 and Ash and Shooti can never have the same bond as Paul and Ash which had Infernape to thanks. At most Shooti would say "well it looks like I'm not as good as you when training Tsutarja, but that's not all I have, go Articuno use ice beam" *Ash's Tsutarja gets knocked out.
I am not sure what Iris is going to do in the anime. If she goes for musicals, I can see a repeat of buizel scenario. Pokabu is not interested in musicals, nut iris tries to dress it up in girly clothes which makes pokabu uncomfortable. So Iris finally realizing this gives pokabu to Ash. You can't say the writers do not like to repeat their stories. And it does not even have to be a mutual trade; Iris could just give her pokabu away without receiving any pokemon from Ash in return.
Again I really can't see how a storyline like this would make Pokabu be used more (unless to play catch up like with Buizel). Remember Buizel was used a lot in the early DP series after being traded, and people complained but once the writers focused on Chimchar/Infernape, Buizel took a back seat and didn't get much at all and then it got completely overshadowed by Chimchar/Infernape entirely. Not even all of Buizel's hard work can be compared to Chimchar/Infernape's hard work.
There you go. That's all I am trying to say, that it is obviously a possibility and there is no way of saying that it would definitely not happen this time with BW.
No matter what the convoluted story, I can't see the writers focusing on one starter like they did with Chimchar/Infernape in DP, there doesn't seem to be time for it and really doesn't make any sense. Hypothetically right now none of the starters have anything to prove like Chimchar/Infernape that would explain why Ash's entire team got shafted in favor of one of these starters.
The only way they'll focus on one starter is when Ash only has Mijumaru thus they have no choice but to focus solely on that starter. But if Ash gets all three starters or two, I definitely don't see the writers not favoring one over the other.
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And as for the Shooti talk....really?
Pikachu can't use electric attacks and Shooti takes advantage of the situation and beats Ash and suddenly the writers aren't treating Shooti like a real rival like Paul?
First off Shooti can never, ever be as good of a rival to Ash as Paul.
Secondly even though that will be the case doesn't mean we should hate on Shooti, like some people are apparently doing. He might not be the best after Paul, but Shooti looks like he will be good enough (although quite frankly I want Ash to beat him every time after this loss but realistically speaking it isn't going to happen)