Hi there Momo,
It will take more than 10 trades for this technique to work, but you will eventually exit with no loss.
Think about it this way:
The losing long trade is now 110 pips against you when you take the first $100 profit with the new short hedge trade. Now you close 1 mini lot from the first long losing trade for a loss of 110pips x $1 which equals $110
Now you are left with a loss of $990 but this time only with 9 mini lots. Now you do the next hedge trade for another $100 profit and now the first losing long trade shows a loss of 9mini lots x 120pips which equals $1080. Now you close another single mini lot from the first trade for a loss of $120, now the first long losing trade reflects a loss of $1080 - 120 which equals -$960
By the time you take $100 profit on the third trade, the first long losing trade (now with 8mini lots) gives you a loss of 130pips x 8 which equals $1040. You again remove 1 mini lot and now the losing long trade reflects a loss of -$910
By the time you take $100 profit on the fourth trade, and you have removed 1 mini lot, the first long losing trade reflects a loss of -$840. What happens now is that, yes, the market does move more and more pips against the first long losing trade, but with less and less lots and you on the other hand keep on taking 10 pips using the scalping technique and removing $100 from that first trade.
Like I said earlier, it won't take 10 minutes or only 10 trades for that matter to trade yourself out, but you eventually will do so. Also the market does not move in a straight line and should the market pull back a bit, it just gives you extra leeway - call it a freebie
Remember that you could snow ball your hedge by locking 10 pips in with your stop and then removing that "banked" profit from your first long losing trade and entering another hedge and so on. After a while you would have 3-5 lots in against your losing trade for no risk as they are all locked and then the following will happen, picture this:
The first long losing trade reflects a loss of -$840, but this time with 7 mini lots. Now you have "snowballed" the hedge trade into a profit of $300 using three standard lots. Now you can remove that $300 from the first losing trade with a huge smile on your face
Just carry on like this, try it first on a demo account and then you will see what we mean.
Thank you for your interest in this subject and please, do not hesitate to throw me with the questions!
Happy trading out there