I think people are hyping this card up a little too much.
...actually glad you brought that up because (for better or worse) I prefer to quash excessive hype.
Just for clarification purposes, I hope these two sections of your posts aren't in direct relation to my various posts about the card. If so, I'm only attempting to find potential uses to the card. If not, then ignore this part completely. ^^;;
Volcanion-EX decks suffer an autoloss when facing Greninja BREAK decks; Volcanion-EX decks have a strong enough damage output to still have a fighting chance against Water Type attackers. They also have solid enough baseline damage coupled with attack based Energy acceleration to handle the loss of the damage buffing "Steam Up" Ability. Losing both, however, hurts quite a lot and not is that what happens when the deck faces Greninja BREAK, but add in Ability based bonus bench hits. @_@ Volcanion-EX decks fascinate me because of how dominant they ought to be... except there are so many overly potent Pokémon in the card pool that (while still clearly a fraction of overall cards release), they create this insanely fast, hard-hitting metagame.
Volcanion reminds me of Naya Blitz from MTG back in 2013 (during Innistrad Block if anyone remembers). It was this extremely hyper aggressive deck that could literally kill someone in 4 turns with the correct set up, but was EXTREMELY reliable on things like a great hand, good match-ups, etc. Now, while Volcanion isn't nearly as reliant on having a great hand (nor is nearly as aggressive a concept as Naya Blitz), I feel like both decks have done (for their respective times) something extremely similar: Top in more tournaments than they theoretically should have.
Volcanion is an oddly unique concept that combines consistency in two different forms: one being energy acceleration and the other being damage output. Typically, decks that do something along these lines have some sort of negative setback. For example, the damage output of these decks may be low or the Energy Acceleration may be there, but not massive in comparison to other cards. Volcanion, however, has solutions for both of these issues while also having these issues all at the same time. "Baby" Volcanion only does 20 damage when it uses Power Heater and technically only attaches 1 Fire Energy to a Pokemon per attack, but Volcanion-EX allows it to bypass its low damage AND "Baby" Volcanion chooses 2 different Pokemon instead of just 1. These little additions have allowed this consistent deck to become much, much more as a strategy because it allows it to do what most other consistent decks do not: Fight back with a "Strong Force" (in this case, damage output). Because of this, Volcanion decks can set up over and over and over and not lose momentum, which is insane in a deck that seems to be based around consistency.
At least, on paper it is.
Now, as we all know, Volcanion is not THE best deck right now. It's definitely one of the "Four Kings" as I like to call them (Yveltal, Volcanion, Greninja, Gardevoir), and personally, I believe it's the second best deck in this Format (people will argue, however). That said, it has flaws. While it attempts to thrive on consistency, it has natural consistency issues outside of normal "bad draws" in regards to Energy Management, proper set-up, etc. This makes the deck harder to play than it looks and I personally believe this is one of the two main reasons the deck hasn't topped more. The other reason I believe this deck, while very successful, isn't closer to being an argument for "Best Deck" is because while its damage output is great (especially for a deck that accelerates Energy), it is both situational (it needs Volcanion-EX to function properly) and the damage output it still not enough for that argument. Yveltal simply outscales it (and we are not getting in to the whole Garbodor discussion here, but obviously that plays another huge factor in this discussion).
Sorry about derailing that. It just reminded me of a discussion I had with my friend about why Volcanion was doing as well as it had been.
Back to the topic of Giratina, however, I feel that it will be a very niche card. As I said earlier, it will be played by people who feel that it is necessary. If anything, I wouldn't be surprised if Trevenant BREAK players teched it for the Mirror Match. After all, while it sounds silly, it becomes an answer to those who are able to accelerate in to Trevenant BREAK first. For example, if I watch you go in to Trevenant BREAK while I'm still at Trevenant, I can drop Giratina, get my items back, and watch you stay under Item Lock while slamming my Tree Fists in to your Trunk. It's a rather subtle idea, but it's an idea nonetheless. Also, Giratina is Psychic, so that makes it even less useless overall in that specific scenario.
I hope you guys are enjoying all the information. It would be pointless typing/sharing all this, otherwise. Still, keep discussion ideas and maybe we can think of more ways to utilize this card.
Take care, ya'll.
-Asmer