Remember though it was a Klingon Engineer who discovered how to defeat the energy dampening weapon of the Breen. Without it the Breen are on an equal footing with the Empire now. The empire never revealed the secret to it's allies either.
Actually the Klingon engineer came upon this by accident when making a adjustment to his ships warp core that was having containment problems.
Because the feds and Romulans use vastly different tech to the klingons they could not make the same adjustment to their ships and a different counter had to be found. http://memory-alpha.org/en/wiki/Energy_dissipator