[mauritzio]

Imho he did not be became better at "painting" but he made better designs for paintings. He trained one important aspect of the whole piece of art, the design. The aspect of applying paint was not trained, so that probably has not improved.

[username90]

A skilled painter isn't just someone who is good at applying paint the way he wants, similarly as how a skilled writer isn't just someone who writes the words he intends to write. The skill includes all aspects required to make great pieces.

[mauritzio]

In the end there is just paint/words. The question how to find and apply the right/wanted paint/words involves many aspects. By training one aspect it doesn't improve the other, but it may or may not improve the overall outcome.