For sure, you could say that Potter developed both James and Rodon.
Alternatively, you could say he was fortunate to have two really good youth team prospects available to him.
Maybe one is true and the other false, maybe both are true. Who knows.
You are confusing facts with opinions.
FWIW, I didn't watch any of the Championship that season so can't comment on the strength of the division or how Swansea played that year. But from the outside looking in, that squad looks pretty solid and would expect it to finish mid table.
Leroy Fer - Dutch International
Oli McBurnie - £20m striker
Nathan Dyer - Premier League winner
Wayne Routledge - Premier League veteran
Dan James - £15m winger
Joe Rodon - £10m CB
Kyle Naughton - Premier League veteran
Pretty solid squad imo.
Why would it be a good move for Potter?
Stepping down from the Prem to Championship, a club that will have very high expectations, uprooting his family.