Well Steve, if it does happen, i guess that is part of a strategy and there can be only 2 cases:
A. either there are two opened positions on different currencies, which is obvious, each position with it's own pip P/L,
B. and the second case where happen on the same currency, here, there can be another two cases:
B1. first if the broker limits the max. lot and there is the need to open a second trade to compensate (been there, so I know),
B2. the second case is that needs 2 or more positions for different SL or TP levels, in this case the whole package belongs in the same strategy, same signal, same entry condition, so, the results should reflect that by averaging the P/L pips.
Well, in the current state it can easily fake the pip count, just by repetitively close the profitable position. For example, if you have +10 pips on 1 lot, if you close it by 0.1 lots, in the end you will get 10 positions of 0.1 lots, each with +10 pips, basically, +100 pips.
At least a 'view mode' that should average the pips would be better than nothing.
Or maybe, as a last resort, a way to manually merge the positions in question, and still being able to see them individually (an collapse/expand button on that group for example).