Validating strong passwords perl

I have a cow-orker who's first name is "G" - he's very used to poorly-validating websites claiming that his firstname is "wrong". I've got another friend/acquaintance who's got a fully legal (self chosen) single name. He has the expected hilarious outcomes with things like Google's "real name policy".

Users are not entering RFC compliant email header values into your form. Typical server-side validation is for REST JSON API calls by third-party apps, and also for parsing freeform text fields like "tell your friends about us". The biggest argument for not validating email addresses shouldn't be that "it's hard".If someone is using an address like '[email protected]', I think they'd expect a message saying 'your email is invalid'; and seeing a message that just says, 'are you sure?' with a 'yes' option would be perfectly acceptable.Better UX in my opinion is to do validation before sending, both client-side and server-side (esp.good for REST JSON APIs), then if these are all good send the welcome email.