The aptly named G-senjou no Higeki is a nine-minute animation by Kuri Yoji, who you might know for the proliferation of his works across MAL's bottom 100. In fact, if you've found this page, the chances are high that you already have an idea of what you're getting into, but courtesy demands I offer an opinion, regardless.
The visuals are standard fare for an indie short with the dementia tag: abstract, chaotic, occasionally vulgar, treading between metaphorical and meaningless, etc. There's room to swing either way on a judgement here, depending on your tastes. The visuals aren't why this short is bad, though.
The defining aspect of
G-senjou is the horrible and probably unethical slaughtering of the violin that ushers in the musical element. I don't have a hyperbole strong enough to stress how bad it is. It's literally just a complete amateur, probably Kuri, slashing away at a string once they figured out the angle that produces the loudest, harshest, most unpleasant noise possible. This lasts for about three minutes, before the musical focus shifts to using other instruments to produce more disgusting, wholly unenjoyable noises. To this short's credit, they're in synergy with the visuals, but something like that becomes hard to appreciate when annoyance or discomfort is the only thing you can feel while watching.
G-senjou suffers from the same issues a lot of experimental, avant-garde media suffers from, in that it fails to find the balance between being artistically-rich, and being enjoyable enough for someone to even foster an interest in unearthing any meaning. And even if you do decide to dig, there probably won't be much to find anyway. All-in-all, an inefficient use of nine minutes, even for a seasoned fan of anime.