Let's say a given key is given like: A major.
Is it better to know how to play the diatonic chords in your given instrument (like piano or guitar) by pattern. For example, in piano I could just know the scale. Then I could just pick out the I IV V etc of the scale, just by moving my fingers around without knowing (or bothering to know) what the names of the chords I'm playing. All I know is I'm playing the "V" as an example.
Is it better to memorize the diatonic chords of each scale by name. So the diatonic chords in A major would be: A major, D major, E major, B minor, C#minor, F#minor, G#dim. and then play these chords on the given instrument?