I'm not sure if they can all directly monitor your MT4 for a robot or not, but they do monitor every command from your end. Many robots will send modifications to SL and TP to multiple trades in a few seconds. Some can open and close trades on different pairs much more quickly than any human can.
Naturally, the brokers also have copies of all the common robots, so know what patterns those use. An evil broker could even run one on a faster data feed to anticipate the EA opening and closing trades. At that point, it would be simple for them to arrange for price to jump a pip against all those anticipated entries and exits.
Hell yes they know! Look, some brokers don’t execute your trade, they just give you a signal. If you win—they pay you, if you lose—they take your money. But they have more then 90% chance that they will get your money. How do they know? - Statistic!
I never thought of that, but it sounds scary. It means that the brokers have the way to "fight" profitable robots!
In that aspect, it is then better to be with a small size broker! The chances that the specific broker would have a large number of customers that use the same Robot are quite low. Of course if you grow your account so much, that they would go through that procedure just for you, it means you have earner already enough out of Forex!
I hope that one day I will be able to trade successfully without the help of robots!
What about ECN brokers? In theory you are not trading against them. Do they really welcome successful robots, as some of them advertise? Do someone has experience with them?
Hell yes they know! Look, some brokers don’t execute your trade, they just give you a signal. If you win—they pay you, if you lose—they take your money. But they have more then 90% chance that they will get your money. How do they know? - Statistic!