Hey!
What do you think you are talking when you say…"blind" vastu principles???
Many vastu principles are found to have scientific basis and reasoning….
Some of them may not be relevent with todays life style….
So what you can do is first of all understand d underlying principle… and then tell the people how it used to be helpful to people in old days and why its not needed now……
But plz respect the old craft of vastu.. Its indegenous to us Indians…