User blog comment:Ficus7/Allowed Technology/@comment-10905876-20140914172227/@comment-12161342-20140914175227

Problem is... what if you have an interdictor field set up and it tries to yank an entire fleet(or even a single huge ship) out of warp? You would need IMMENSE amounts of energy to be expended INSTANTLY, because basically you are not just stopping a warping ship, but fighting ITS warp core too, as well as sustaining the interdiction field. Now multiply the energy required to stop ONE ship and multiply it by a fleet, and you have a power problem on your hands(and that's ignoring the baseline power consumption of basic life support, sublight maneuvering, various critical systems, and weaponry).

I could see interdiction cruisers working only if they are basically massive power plants crammed inside a hull, and while they are stopping ships they cannot defend themselves, maneuver at all, and can only sustain the field for a short time. Also, the time the field can stay up would be decreased on a per-ship basis for each enemy vessel it is trying to detain.