This strat mostly effects the Fake Credits category because Sneaky Spirits is the only mini game that has a large effect on a run's time. All of you know that when you hit a ghost with an arrow, the game triggers a slow down animation, and these animations have different lengths depending on the type of ghost.
The mini game has a total of 8 ghost to hit The 4th and 7th ghost have the longest slow down animations when hit, and you can tell with the build up leading before you have to hit them
So, if you hit all 8 ghost you'll finish the mini game in about 59.8 seconds.
If you skip both the 4th and 7th ghost, you'll finish he mini game in about 54.8 seconds (5 seconds saved). Missing two ghost will guarantee an "OK" as well. Miss anymore than two ghost and you'll fail the mini game.
But there is a way to actually miss three ghost and still pass with an "OK". You have to hit 5 ghost with "Perfect" timing (rainbow star circle). At the result screen you'll be given a score of about 58, then a bubble text comes up saying "But there was some good parts", and will bump your score up to about 60 which is enough to pass the game. BUT THIS ONLY HAPPENS if you can hit 5 ghost with "Perfect" timing.
So this is the most optimal strat: ghost 1: perfect hit ghost 2: perfect hit ghost 3: perfect hit ghost 4 skip ghost 5: perfect hit ghost 6: perfect hit ghost 7: skip ghost 8: skip
You'll finish the mini game in about 52.6 seconds, a whole 7 seconds of time saved.
If you get just a single "non perfect hit", you'll will have to continue with only skipping 2 ghost instead of 3
¤edit¤: spelling errors