Close Order Function Confusion

[Chance Watkins]

Not necessarily a troubleshooting topic but how come with the MQL4 language there is the stigma of including slippage in the CloseOrder function? I don't think slippage is a factor when I manually Close an order so why do you suppose slippage is absolutely necessary for an automated program? All it does in my opinion is decrease the accuracy of the trade. Is there a way to emulate the manual closing of an order without slippage in code? I realize that obviously an EA is only going to be as good as the computer, server, etc it is running on but is there still no way to emulate a manual close order? I apologize if this is not in the right section :P Don't know what it falls under. Thanks :)

[William Roeder]

Chance Watkins: stigma of including slippage in the CloseOrder function?

1. Because most people don't understand the value — only applies to dealing-desk brokers and not ECNs.
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2. That at the time most connections were like 5 Kbs, and if the market moved faster than your connection, you might not want to open/close. So a slippage of a couple of pips might be reasonable to allow the EA to skip the trade and re-evaluate.
   
3. Just put in a large value — what's the problem?