@Ephesians3-14 "Why would I e-file his 2020 tax return this afternoon and disqualify him from receiving a $2,800 stimulus check?"

Maybe because you advised him of the possibilities and let him make the choice?  But you always ask clients what to do, rather than telling them what to do. So your question is really to us, asking if we keep our clients in the dark about their choices.  

No.  I don't.