It is a good feature for spam prevention. But with some tweaking.
For my situation, client's server is down ( obviously the domain also down ). Now he comes with us telling his login to blesta not working, seems it is due to the dns query. I tried to reset the password and it failing with "Invalid email address". So in this condition, it should have except the condition. Since the email address is valid and at the moment domain is down.
If I am a hosting company (a test scenario ) and using blesta for billing and customer domain suspended due to billing. So in that case customer is in deadlock situation. Since he can't get an option to login to hosting billing login for the payment to bring his domain up. So making adjustments in this feature is a good option.