The fact that no one is dying on the really slow ones is kinda disproving the "hyperspeed theory" that some people have.
Not quite.
The problem with this experiment is that the only data you have for evaluating is the number of deaths. Deaths always occur at extreme values of playing pressure. The last two (or four) scripts will have by far the highest death count because the variable bullet speed means the pattern switches between easier and more difficult phases. As the difficulty peaks on the difficult phases, you are more likely to pass the difficulty resulting in death as if the pattern was more constant.
Now, this "Hyperspeed Theory" (stupid name, imho) is all about other extreme values. The reason why your slow attacks seem easier is because they were not slow enough. If you set the bullet speed to 0.1, for example, the bullets would be so slow that you'd get a face full of wall. Slower bullets mean the space between the bullets of different firing moments is reduced. If you have a pattern that requires you to move through this space, lowering the bullet speed will increase the difficulty once approaching towards extreme vaules. That is why VoWG easy is more difficult than un normal: You have to maneuver through much smaller gaps.
On the other hand, increasing the speed of bullets reduces the time you have for reaction and thus will peak the playing pressure (and thus the death count) if it surpasses the border of usual human reaction times. This, however, depends on how good the player is in this kind of thing. For example, easy mode players will probably get overwhelmed by the sheer speed of the last four patterns, while lunatic players wouldn't have a problem because of their trained lower reaction time. If you increased the speed even further, to, say, 20, the cards would become entirely luck based and would yield a high death count.