The author claims that plain text emails are "less likely to go into the 'Promotions' tab in Gmail" and are "less likely to be caught in spam filters," both of which might increase open rate.
> If I turn them off, half of my mails still get sorted somewhere that I cant see.
When the tabs were first enabled, I deselected all of them except the primary tab & haven't had any problems. The primary tab is essentially my one tabbinbox. I did...
