If a school is consistantly ranked in the top 3 at every grappling tournement that is a good sign about the quality of the school correct?
Depends. If youre referring to the top teams at Mundials and Pan Ams, its an accumulation of 100's of affiliates for Alliance, Gracie Barra, Gracie Humiata, etc... But generally yes, any of those gyms and its affiliates are a safe bet for being a great school.
It depends on what TS is looking for. Schools with good competition record could equal as instructors paying more intentions on his competition studs than the average joe students. Once again, it depends on each individual schools.
It could just mean that the school is huge and sends a lot of competitors, not that the school has any particularly outstanding people. Some competitions also count childrens' division victories into the team points as well. But usually if a BJJ school is big, that means it is doing well as a business, and if it is doing well as a business, that means it is offering quality instruction.
This. I'd probably add that a school that doesn't regularly win or even place at big competitions isn't necessarily a bad school. It simply could be that the school is small. There's a LOT of weight and experience divisions, especially at something like GQ or NAGA.