Phosphate impact on corals?

[Hans-Werner]

According to Einstein everything is relative .... To be serious: Take the same coral and let it grow under exactly the same conditions except phosphate and you will notice a difference.

 

[Graffiti Spot]

A lot of people are running tanks without worrying about phosphate levels now and getting good results. Not many are complaining of any of the above issues although I don't doubt they can be a problem. I would say the main differences I see in mature low and high phosphate tanks is color and not much of the other issues. I don't doubt that the other issues can arise but it's not often that one becomes a problem if everything else is in line.
It's all very odd to me because I have always kept phosphates in check so I have always been curious about the topic and some of the issues that have been said to be caused by phosphates.