Good idea IF we can get sufficient participation. Several million Americans exercising their right to open carry where they can legally do so would be very enlightening for many who are oblivious to these issues. Those 'behind the lines' in states with more restrictions could do the 'empty holster' carry and explain why it's empty.
To be successful, there would need to be a substation number of people involved, and they would have to avoid going commando, mall ninja, etc. What we need is millions of normal, hardworking, solid citizen people making it clear they want their right to keep and bear recognized.