This is a tool-assisted speedrun. For more information, see http://tasvideos.org/1116M.html
As you might know, Konami realised they went a little overboard with the difficulty of the arcade version of Gradius III, so the SNES port got noticeably easier (and laggier). However, it still remains one of the hardest and most unforgiving shoot 'em ups released in its era.
This is Cpadolf's take at the shmupping carnage, resulting in a significant improvement in both speed and style over