There are still callers who omit sending my call before theirs. Only their calls like in DXpedition QSO. Actually, some of them could be calling not me but the other, always certain DX, in split frequency operation. In that case, after sending him the necessary informations and turning to reception, I would find no one there and, what is worse, that guy went on calling with only his own call.
If such a caller is off my frequency or not in time, I would not respond to him. I might have to ignore such a caller even on the right frequency in time. We should tell beginners that the pile up game is not the ordinary way of communication. It is an anomalous way. We should advocate the traditional way of communication on CW.
Of course, if the other you are calling is aware of your calling him, it is not necessary to give his call before yours. It could be even redundant especially when the condition is not good.