Did you play through the game in one take without dying or did you replay some stages and cut'n'pasted it into the 'final - not dying once' longplayer?
A while ago I got rather fed up with all these people talking about Project-X like it would be one of the hardest SHMUPs ever since that wasn't exactly how I recalled it... so, I started playing the game again just to see how 'hard' it actually was. What I found out was that I didn't find it hard at all... merely rather time consuming; memorizing the levels and learning how to best deal with their harder parts. Project-X, as of today, feels like a very average leveled SHMUP with 'trial & error'-gameplay an absolute must to complete the game. I never completed my project to play through the game without dying once... but I can without any problems reach the fourth boss without dying and I am pretty sure if I was to 'learn' the final stage aswell I would complete the game wihtout dying once. And I am not even that good at SHMUPs... (the only one I have completed without dying is LifeForce on the NES... but besides LifeForce I can hardly beat any SHMUP without using many credits along the way).
Of course. We all play differently and we all are good at different aspects of gaming... so what is 'easy' to me is of course not necessarily 'easy' in general... and vice versa... but still, I can't really see the incredible 'toughness' that Project-X supposedly has to offer.
Really nice longplay, by the way! And if you managed from beginning to end without dying (without using any savestates or whatever), congratulations!