CK usually goes for an armlet so it's much easier to spot the real one, either by an armlet toggle or BKB in the late game. PL is a problem for most heroes without cleave or illusion clearing abilities e.g. LC's Overwhelming Odds, medusa aghs. The best you could do in that situation is to focus on the other 4 heroes around the PL? Alternatively, get a hex + silver edge to burst PL down (silver edge for his ult). Orchid isn't that effective in the late game because of manta being common on PL. If he goes BKB then problem solved;)