We're trying to reduce our email bounce rate and often we get people mashing their keyboards. Here's a few example "email addresses" on our suppression list:
aaaaaaaaaaaaaaaa5@hotmail.com
aaaa_a@hotmail.com
991022865@gmail.com
725668844@gmail.com
82665@gmail.com
81c3988a@mailna.me
I wonder if it's possible to write some sort of php function to tell how likely the first part of an email is to be "mashed"?
Edit: We do send confirmation emails and run them through a 'validator'. Having a confirmed email is not necessary to use the site though and I'd rather not send them a confirmation email if it's super-likely to be mashed. Trying to reduce the bounce rate on confirmation emails, so we can reduce our costs of sending emails to those that are confirmed!