When I did my exam last week, I went in knowing I couldn't do a brain dump. So I spent 5 minutes going through the tutorial, started my exam, and did the brain dump as soon as I started the exam. If you go into the exam treating it as a 3 hour and 50 minute exam instead of a 4 hour exam, then you can take the time to do your dump, and just pace yourself slightly faster to complete the rest of it.
I was given my paper when I was seated, and told that I wouldn't be able to write anything until I clicked the "start" button. Although in my case, I just had a bunch of EVM formulas, and in the end, there only a handful of questions that required EVM formulas...