The phrase "as he refined" is correct and usable in written English.
It can be used to describe a process of improvement or enhancement that someone is undertaking.
Example: "As he refined his skills, he became more confident in his abilities."
Alternatives: "as he improved" or "as he honed".
As he refined the character, his language grew vaguer and vaguer, an evolution that was actually an articulate comment on the decline of clarity in political rhetoric.
Perhaps the greatest victim of his megalomania, Farrell suggests, was his wife Pat, who stood by his side as he refined his gift for political devilry.
"Now turn and step, and step with a little hop," instructed Mr. Tune, ever the perfectionist, as he refined the simplest of routines — the curtain call bow — an hour before opening night last week.
With neutrons it turned out that that was completely different, and we were very pleased and happy to find that we could learn things about hydrogen-containing structures". As he refined the scattering technique, Professor Shull studied the fundamental properties of the neutron itself.
Billy told Heather that he had undergone sex-change surgery, but as he refined the story over the next years he would claim that the process had only just begun, that there was something down there, it was small, but it would get bigger by the time all the operations were completed.
The chief designer, Ralph Gilles, 34, said he kept the word "noble" in mind as he refined the design -- meaning noble in the vein of classic Duesenbergs, Rolls-Royces and Chrysler's original 300 of 1955, a powerful coupe with understated styling and a reputation as "the bankers' hot rod".
"The homers and the hitting for average, that's going to come as he refines his game.
And Pettitte has increased his tempo, working faster and faster, as he refines his complementary pitches to reduce his reliance on the cutter.
But even as he refines the use of the technique for treating pain, deCharms is now testing it in patients with anxiety disorders.
Jennings strongly condemned slavery in his inauguration speech and as governor, he refined his stance on the institution.
Before I had time to thank him for what I regarded as a compliment, he refined his complaint to a point where it barely existed - or at least applied only to what he regarded as my less than generous attitude towards the chancellor of the exchequer.
