Hi,Does anybody have any thoughts on whether one should have more than 1 cross currency (xccy) discounting curve curve per currency? My current problem is this:For each currency, I have just 1 xccy curve. So for USD this is just the Fed Funds curve, but for non-USD currencies this is a curve built from the domestic OIS plus a xccy spread against USD. So for example, my £ xccy curve is built from: SONIA + £/$ xccy spdand my EUR xccy curve is built from: EONIA + EUR/$ xccy spread.On this basis, when I'm pricing a £/$ xccy trade, I use my standard (non-xccy) curves to project out my forward rates, and use the relevant xccy curves to discount the resultant cash flows. For an on-market spread, when exchange of nominals are included, both sides of my trade PV to zero, and everyone is happy.Similarly, for an on-market EUR/$ xccy trade, both sides of my trade PV to zero.So far, so good. Unfortunately, if I now trade a EUR/£ xccy, the fact that I'm paying EURIBOR flat on the EUR leg means that I have a non-zero PV on this leg. This non-zero PV is negated by an equal and opposite PV on the £ leg, and so the total mark-to-market on my trade is zero. However, the fact that I have equal and opposite m-t-ms on each side of the trade, in two different currencies, means that I effectively have an FX position in EUR/£. For normal size trades, this is a material position, which I have to hedge.I find all of this conceptually troubling. I've done an on-market EUR/£ trade, which has given me a spurious FX position (if I had defined my £ xccy curve against EURs instead of $s, this position would not exist!). I am forced to conclude that I need several xccy curves for each ccy, e.g. for £ I would have to have a £/$ curve, a £/EUR curve, a £/JPY curve etc.. Yet most people in the market that I've spoken to don't do this.Any thoughts?