The creative process is a demanding master.  In my experience, artists — and speaking is high art — seem to work at a creative peak about four hours daily.  Yes, we're all different and must find what works best.  I do my best work for an hour or two before break time.  continuing beyond that leads to negative work:  that which is done so poorly it must be redone... better.  That written, it's time for a break.  (Interesting.)

I'm back.  Mind afresh; coffee refilled; ready to complete this page.

There's nothing more to say on this.  Know yourself.  Work when creativity is flowing.  Take a break when it's time.  Enjoy the process.

As I write this I recall a cartoon from long ago:  Two explorers standing in a pool of quicksand; one up to his knees; the other up to his neck.  The one up to his knees saying, "That's where struggling gets you."