How could Sephiroth take on his own form when he's frozen in mako?No...because it's him. Sephiroth would assume the form of Sephiroth because (say it with me) it's him. That is who he is. There is logic to Sephiroth taking on this form, there is no real logic to Jenova taking on the same form.
Where does it even remotely suggest that? That is pure assumption. How can you take away such a being's power? Her cells still work...Oh please, whatever true power Jenova had is lost all throughout the game until the reunion, and even then Sephiroth is the more powerful of the two. What did she do during the Cetra ages? Shapeshifted and spread a virus? Big whoop, clearly she's "one of the most powerful beings ever".
Sephiroth controls NOTHING. He believes Jenova is his mother, he obeys her. She controls him!Well, that can be explained in two ways:
1 - Basic defense instinct
2 - Sephiroth still controls the pieces after dropping them.
Even if it was an extremely high concentration, there's an infintely higher concentration in Jenova herself. Sephiroth admits himself that Jenova is what he considers "all powerful." And, yes, I'll get you that quote, but I'm in school now and don't have the time.During FFVII? Sephiroth. We don't know how much Jenova cells were injected into Sephiroth, but it was likely a high concentration. Either that, or the extra boost came from being injected while in the womb. Now, no doubt Jenova has strength, since those who carry her cells "inherit" this. But what else? She can shapeshift (supporting the theory that we're following Jenova's body, whoever's controlling it). She can spread a virus that turns people into monsters. Ok, what else? ....god knows, that is all we know of Jenova's "power". Who's to say Sephiroth didn't directly "inherit" Jenova's strength, carrying her cells before birth? So he could be just as powerful as her.
It's not sloppy. It's great story-telling. It actually makes you...how do you say it? Think. Jenova controlling Sephiroth is extremely logical, and supported by in-game facts. What you're saying is not both.They're "factual" in a sense, but they're not logical. The game is from Cloud's perspective, so we never get to find out anything about "Jenova's true power" and never even get a little hint that she's pulling the strings? It would be sloppy storytelling, very sloppy. FFVII isn't always perfect, but it never falls to those depths.