This is to XxACDinho10xX and anyone who still thinks friendly AI (delta and riot sheild squads) on the mini map are other online players.
1) Take a little extra time to look at the actual game and not just the mini map. They have green triangles over their heads, not gamer tags, so you can tell their your AI and not the enemies, not cause theyre other online players.
2) Robert Bowling has stated SEVERAL times in video interviews and on twitter that survival and all of spec ops is only 2 player because they want that 2 player team work feeling and just you and one other person fighting off waves of enemies and going through missions.
3) EVERYONE but you knows this already, dont feel embarrased (even though its really pretty embarrasing) just play it off like you knew the whole time or say you have some sort of mental disorder