Holding an emini position overnight

I apologize if this question has been answered already. I was googling some information about trading overnight positions for the ES on Globex. I was interested in the margins required. And I came across this answer:

"hey guys,

holding a position in the emini(s) overnight really comes down to the 15min window that the Globex shuts down to settle books. that 15min window is further expanded by a total of 1.5 hours until trading resumes and they open up the pipes for trades. on most contracts, isn't that 6pm EST or 5pm CST?

so really holding a position overnight might not be worth the problem, and an alternative would be to simply close before the end of session, and come back at the beginning of session (say, take your wife out to dinner and come back to the office over the garage) and re-establish the position.

that is a synthetic solution"

Does what he say had some truth to it? Because it kind of makes sense? Any information will be greatly appreciated.

There's a cost to closing and opening the "same" position. First there's the commission that you'll pay to the broker and second there's the bid ask. You'll have sold at the bid and bought back at the ask. See the The Bid/Ask Disadvantage.

I think what you need to determine above all else is what your trading strategy is. This includes the time of day that's best for you, your risk tolerance etc. BruceM, for example, has said that his most profitable time of the day is in the morning (I think). This might be because he's fresh and bright at that time of day or because the strategies that he employs work best during those hours. Getting a good night's sleep is important to be able to function at 100% each day. Holding position overnight may rob you of that sleep.

Just some thoughts...
Thanks for the heads-up DayTrading. Is this true though? Technically, could I wait an hour and a half after RTH and trade "overnight" without technically trading overnight--having to have the huge margin in my account? I'm asking because I look at a set of free charts online that provides the overnight action on it's charts and it gives me a clearer picture of everything. I'm also getting a live feed now, and it has a lot of gaps on the charts as far as the daily chart is concerned. Because I notice that if I was actually trading, on a lot of trades, I would have had a better position if I would have gotten in somewhere AFTER RTH. So technically, could this be done?

Do what I do. Just hold the position and ignore the Margin Call. Seriously I have done this. If there were a trade I wanted to hold overnight (I usually don't) I would just keep it fully expecting an email requesting an additional deposit. Depending upon the size, the frequency in which you do it and whether the trade went badly against you. your Broker probably won't liquidate the position.