I completely forgot about this, and yeah, that's actually really bad, lol. Does anyone remember Re: Coded's secret ending, where Mickey bassically deduced where Ven's heart was (which "just leaves Terra", according to Yen Sid in that very scene)? That was supposedly because Mickey finally saw Roxas for the first time and picked up on his physical similarities to Ventus (with them bassically being identical and all), as well as Data Namine mentioning how both Ventus and Sora shared "a very special connection." Both of these things would've been what clued Mickey into the fate of Ventus' heart, hence why he's so sure of where it is by the end of that game. And we know that Mickey recorded down *specifically this information* in his letter to Sora Riku and Kairi, and the scene of them reading it was shown and extended no less than three times across the series. So what gives? Did Mickey not include anything about his conclusions surrounding the potential whereabouts of Ventus' heart in his (surprisingly detailed) letter despite Namine explicitly telling him to do so? Did Riku not put two and two together after reading this and seeing Ventus, Roxas, and Xion in Sora's heart at the end of DDD? Or are we assuming no one told him Ventus looked just like Roxas? Though we are talking about Mickey, so who really knows what he decided to leave out. Either way, Mickey and Yen Sid still should've known at the very least by the time KH3 started, so why was it Vanitas and Ienzo of ALL people that had to "reveal" this information to the protagonist when it's finally time to rescue them? And even then it affects nothing since Sora refused to inform Aqua at the moment of truth (and Ventus would've revealed himself anyway, though it was pretty obvious after all Sora's involuntary outburst about saving someone he admitted to not even remembering), and I still don't fully understand what was going on with Roxas since all of that happened off screen.
Also, I'm kinda dissapointed about what they did with the build up regarding Ansem's data from DDD. I thought, based on his words to Aqua in Blank Points, it would've been used to help restore those hearts within him, not just reaffirm something we already know. In reality, the pre existing data saved of Roxas on the digital Twilight Town (data that we didn't even know existed up until it was brought up) did more for the actual process of restoring Sora's Nobody than the data from DDD did.