First, please excuse me in advance for I am not a pro musician. Playing music is only a hobby for me.
I'm learning how to play the acoustic guitar like Mark Knopfler in his solo career. In this interview (3:36), Mark says that he began with a Folk picking technique, but later began to play like "a Ragtime piano" style (4:00). On some other videos, he also calls it "barrelhouse piano".
My question is: what is the difference between the two styles? In both examples, I hear him playing 4 bit bass, and the melody on top, either together with the bass notes or in between, just like in Folk music.
Does he simply mean that instead of just repeating arpeggio patterns he plays a whole melody?