Watch the Horn Lines 1-3 online guitar lesson by Matthieu Brandt from Jump Blues
In a band setting, every musician has a distinctive place. Within a song this place can change: backup to solo, full chords, riffs, etc.
Leaving space is important, especially when playing accompaniment. Hammering away bar chords on every beat is a no-no. But you do want to make the harmony clear!
Imitating horn players is a great way to make a tasteful accompaniment on guitar. Often you use partial chords, sometimes with slides, to sound like a complete horn section.
Fun and impressive!