It means that player exploited his potential to level = 1,700.
So if his potential is below 1,700 it means that he is capped already. And if his potential is above 1,700, it means that he isn't still capped.
You can write future skills (and test many versions of skills) to check how long You can train him, or how good potential You need.
Allstar = 6,000 - 6,999, etc.
Wow. This is going to be very helpful.
Is there a website that explains this tool? Like where can I find what the cap number is for Star and HOF and such? You show Allstar above.