I have not heard of major safety issues in Europe as a result of mechanical being deemed subject to compensation. Also, I agree to some degree that a very slight increase to costs may occur due to compensation but Ryanair is still flying people for $30 so I think the impact on fares is overblown. Not including mechanical in compensation opens a huge loop hole that we all know airlines will take advantage of. Everything will be cancelled due to weather (apparently anywhere in the network) and mechanical! Also, if airline one has major costs for compensation and 2 others do not then the costs may come out of profits as opposed to hiking fares that may not get matched.