I suppose all we've had growing up have been the edited tour footage and CDs and we've been raised with this idea that X-Japan is infallible and amazing and wonderful, and of course they are and always will be- at least to me. Now, however, we have them back as before and everyone has a phone with filming capabilities and we can film each and every moment and capture every slip up.
I've heard and seen footage of Pata playing X and totally, and I mean TOTALLY, fucking up the solo to the point where it was painfully obvious he was drunk out of his mind, and I've heard and seen footage of hide botching a solo and being late, but you have to dig to find those since a lot of the footage nowadays is the perfection edits.
I agree with Feudal. I like Sugizo and I think he's a good guitarist, I've heard him play the solo perfectly and I've heard him be sloppy with it a bit. Same with Pata, Heath, Yoshiki, and Toshi(he's missed an entry or two). They know the songs and know them well, but to err is to human and I think we just gotta be accepting of that rather than scrutinize every second of every piece of footage we come across.