Anyone who says they could 1LC PoFV is either a god or a liar.
It's probably harder than GRT no-deaths, if at all possible. In the first round of the final stage, not only is Shiki "invincible" (as everyone knows), but the amount of bullets you face is also much higher, for whatever reason. I won't deny that first-round Shiki was very, very poorly implemented, but some people take this single instance of (very) bad design and rampant unfairness and treat the whole game as if it suffered from similar stuff.
I can 1cc it with half the cast 80%+ of the time, and about 95% of the time with my preferred chars (the 5% failure rate accounts for playing more than half asleep), and I'm no Donut or Baity or Jaimers or Sapz or Kefit or Veronica or bjw or any other freak of nature, I can't capture Scarlet Meister or Scarlet Gensokyo, I can't survive Asteroid Belt for more than five seconds, I still haven't captured all the Last Words (curse you Yukari!), heck, my reflexes are
below average as far as I know, not below Touhou player average,
below average person average, and yet despite all of this PoFV is stupid easy for me so I'll just make the "lol hi I'm donut UFO lunatic is easy" face at both of you.
[00:18] <theshim> how the crap are you supposed to beat shikieiki
The same way everyone beats every char that's giving them trouble: watch some replays and mimic whatever you see.
3cc'd on the LAST life of my third credit. >_<
If I remember correctly, the AI skill level resets every time you continue. I'd need confirmation on this, though.
Also, if you would (could - damn bug) upload some replays, maybe I could just point out what you could possibly be doing wrong.