You would always close by 4pm regardless. There's no thinking or hoping on this trade. You're simply riding the day traders from 3:30 to 3:59pm. Never hold over to the next day.
You think you have a chance don't ya? At least the casino will provide a comfortable seat and air conditioning and a drink. HFT's are locked onto stocks like no other. You're only chance is buying some penny stock and winning the stock market lottery as they announce a drug approval or buyout or some other deal. Otherwise you own BofA up 15 cents, down 30 cents, up 30 cents, down 15 cents. Stock market is a controlled game. The only stocks let loose are those with pending BIG news which will 25X volume in one day.
Like printing money. I'm amazed people don't see it. You don't even have to be a trader or knowledgeable about stocks. 3:30 is the cattle call for traders to exit long positions. Just short it. I've never been more serious in my life. Had you been doing this everyday, you would be up to choke an elephant.