In the all blue coins category, if u were to collect 2 stars in a course (e.g. whomps) would u need to collect all blue coins twice or can u just collect some blue coins in the first star then some in the second?

I think that you should collect blue coins only once and not twice (like in 1000/500 coins).

So if I was to get both stars in PSS, I’d only need to collect the blue coins in one of the stars?

probably,yeah!

ok

Ok cool thanks. The reason I was worried was because the WR holder avoided using similar optimisations. Hopefully a mod will confirm

Sometimes it’s a good thing to look at WR videos for info but not all the time cause you can get easily confused

I guess what you mean is something like enter level, get plant coins and then cannonless, reenter level, get the switch coins and then wild blue. This would not be allowed, as the rules state "All blue coins in a given stage must be collected in one segment and you must get a star after all blues have been collected.". One segment means you have to enter the level, get all blues, then get a star. Reentering the level to get another star will not require you to collect the blue coins again, though.

So if I were to do wild blue and collect every blue coin, then come back and do cannonless it would be allowed?

Exactly. The only important thing is you collected all of the blue coins in one session at least once and then got a star after getting the last blue coin. Also SBLJ is not allowed as category extensions go by 16 Star rules unless specified otherwise.

ye basically what Celediev said

enter stage -> get all blues -> get star if you come back for another star you can get it without collecting the blues again