umbrella rigs....

[g00se]

So I was fishing today with a 5 line umbrella.. 7 inch yellow shad..

my friend and i were trolling from an 18 ft. catamaran.. not exactly easy, but it got the job done..

I had multiple bites, but only landed one fish.. all shads were destroyed except for one, so i'm assuming they were all blues..

the bites seemed to happend when i was moving i'm guessing close to 3 knots..

was i doing something wrong using the umbrella that i only landed 1 fish? i thought i might have been going to fast, but i got no bites whe i was drifting slower than 3 knots..

4 of the 5 shad have just behind where the hook was ripped out..

and ideas??