For a more fair comparison, I'll point out that the "skynet" Heroku outage you cited would have caused roughly 16 hours of downtime for the particular type of application used by the OP (a static site with no database), not 76.
Jekyll requires deploys to publish new content, and deploys were down for 76 hours. So, partial outage.
My point is if uptime is your goal you should go with a proven solution. Relying on an unproven custom setup to be 100% mistake free smacks a bit of young engineer hubris.
