I have profited from reading Derek Sivers' notes about some book, when available, to get a feel about what is inside and if its worth the time.

The one you guys are talking about: https://sivers.org/book/DeepWork

Meta: something I found interesting about Derek is that he welcomes mail from anyone: "Please email me at [...] for any reason. I reply to all, and much prefer email over social networks. "

It is. I can recommend it having read it a few weeks back.

I've also found helpful to use task systems that impose a hard limit on current work. I use a simple kanban table in org-mode and it works great to get me doing important stuff.