I was in a jam session a couple of years ago with a few local musicians (ye might remember who ye are) and we were hitting a wall. We had been jammin’ for a while and had a few good ideas (which are unfortunately all gone now!) but we were struggling with one of the ideas. We just couldn’t figure out where to go with it. Everyone was throwing around ideas but nothing was working. One of the guitarists just pipes up and says “Let’s start playing and keep playing it until we’re bored senseless of it. And then, when we’re bored senseless there’s a good chance a new idea will pop into someones head.”
We tried his idea and we were a good 5 minutes jamming the riff over and over, boredom had set in. Still no one knew where to go. I know it sounds cliche, but something just happened. We found where to go with the song.
I think in the initial stages of jamming and writing a song you need to think less to achieve more. Just see what happens and where the music takes you. I agree it is a strange concept but it does work. When I sit down and press record to jam new riffs at home I just look out the window and start playing.