Me and my brother have a slight modification to this strat. What we do is we stay in the spawn area until we have enough for the MP40 (one player with 1750+ and the other with 2000+), camp there until one person gets 1250, then hang out on the room by the power.
Then, when we each have about 4-5k points, we turn on the power and head for jug (This is usually by round 5-7). After that, we wait for someone to have 750 points, if not already, and buy the boat that leads to the bottom of the lighthouse from the jug boat.
Then, we wait to each have 3k points, and then open the door to PhD Flopper, and then from that room, to the inside of the bottom of the lighthouse. We then sit outside of the lighthouse and flop until we can PaP our pistols (Usually by round 9-10).
Then, one person flops whilst the other goes to the bottom of the lighthouse and loops around until there's a train. The reason we do not open the door from the outside to the inside directly is for better zombie flow. It makes looping much easier, and we can open the door to the slider/speed cola/sickle as well without a problem (having both doors down there can be hazardous sometimes).
Then, at about round 12-15ish (when we both have >10k points), we go for the box for either a scavenger or vr-11. The person with the scavenger shoots all of the un-papped bullets at George (if there is enough leftover to PaP), and then PaP's it. His job is to do the looping. The person with the vr-11 (or any other weapon if a vr-11 is not wanted, since PaP'd, it seems to respawn George at full health) is the one doing the flopping.
It got me and my brother to round 26 (Died getting my brother to Jug, he went down 8 times cause he thought he was beast with the PaP'd ballistic knife + sickle).
Edit: Oh and if you get a ray-gun or other decent weapon from the box, you go shoot all of its ammo at George