"Knowing that an address is syntactically valid doesn't do anything to confirm that it will reach the intended target." However, knowing that an address is syn

"Knowing that an address is syntactically valid doesn't do anything to confirm that it will reach the intended target." However, knowing that an address is syntactically invalid does confirm that it won't reach the intended target. If you don't mess up the validation. Might be better than having the user wait infinitely for an important transactional email that will never arrive because of a dumb typo.