Well you're increasing size and reducing R/R by placing the add and increasing the potential loss on the increase. Unless it's explicitly an increase in vol in the underlying (accounting for) then I would not do it. Just IMO. My feeling on adding is that you should allocate to an initial size commensurate with your edge (Kelly, et al).
You need strong momentum for this and at the first sign of it slipping away you must exit, it's the only way.
ok, I'm flat these kind of trades don't happen that often, but it allows me to reset when that net liquidation value hits that nice round number target, I spring into action and take it no questions asked ib TWS makes it very easy, I've done it many times in the past hit "cancel all" go to "fx real" in the account window right click on one of the currecncies and click "close all non base currency balances" it will ask you "are you sure?" and then close everything out at the market you know you got it when you look at your margin, and like right now for me it is 0.05 USD. this one just creeped up on me, hit it after hours on a WED evening it's a bitch when you do it on a Wednesday morning, because you never know what you are going to end up with the main reason I wanted to get flat was, my short eru.usd was quarantined because it was my largest loser (even though it was my smallest position) and according to my rules it would never get added to again unless something else really went to hell.
so maybe I have answered my own question when it hits the target get flat, zero, zilch and reset in a high energy profit situation just trim back to the minimum starting positions
well, that didn't take long, I'm now long some aud.usd at 518 man, that was one big orange candle down on the 15 min one day oh well, I am back in the game I never even got a chance to get completely stoned everything else got cancelled and replaced since everybody else seems to be so enfatuated with eur.usd, I am trying to sell some at 1.30745
everything except the Cad got hit last night, I was sleeping like a baby, since I have been working on the garden out back during the day I don't like it any more than you do, but I just had to sell the usd.cad at the market to get evened up so that makes me 1:1:1:1 long aud.usd short eur.usd short gbp.usd short usd.cad with a limit in on everything except the gbp.usd, which at the moment is quarantined, because it is my largest loser (but if eur.usd takes first place in the losers race, the eur limit will be cancelled and I'll try to sell some more gbp.usd.) aw man, that happened fast, before I could even post, my eur got hit, so now it is my largest loser and twice the size of everything else oh well that puts gbp back in play, I'm short from 5345 with a limit in to sell the same amount at 5410
ok, but don't try that with just one pair. It can drive you down to the depths of despair. My short eur at 3088 is my largest position and largest loser. It will never be touched again, off limits, quarantined. Until it starts fitting in to whatever else I have on. I've been short that eur for weeks now, and it just keeps going up. The only reason I am still alive is because it eventually became my smallest position. one rule that turned it for me to the better is, "never add to your largest loser." Just that one rule alone can save you a lot of grief.