[gcr]

Huh? Ctrl+F "isolat" doesn't show any results.

Setting DNS CNAMEs to a Heroku-provided name make sense. They might make underlying infrastructure changes; that's why you're using them instead of rolling your own on a VPS.

Having more than one worker also seems sensible.

The article stresses that these checks are all optional. You don't have to pay double for anything if you don't want to.