I recently made a video of AE kiting here. Its with 7 mobs, I couldn't find any more at the time because it was crowded, but I have done ~11 with red con gnolls/DB aviaks. Hope its helpful for anyone who wants to see what its like.
I am positive the OP mentioned these things but I am going to reiterate what I have learned from the short duration that I have been kiting with a bard on p99.
1a) Mobs have incredibly huge hit ranges when you are running straight. I specifically left a clip in that demonstrates this. When I pull the first mob, I will zig-zag away and not be hit. Shortly after you will see me running from the same mob and I am running straight and he will hit me from a ridiculous distance (~:40 into the video).
1b) NEVER RUN STRAIGHT. Even if keeping your circular motion mean you will be closer to the mobs do it.
2) The distance that the songs can go is so short that you must kite in an oval. Ideally the song will be cast during the time you are on one of the small sides of the oval, as that is when the mob is closest to you.
3) Never run straight.
http://www.youtube.com/watch?v=aS_ag6U1Z6U