So I was just playing a game with the Beyond Extended Universe mod and noticed something very disconcerting. I had formed a number of mutual defense pacts, although of those perhaps one or two actually had enough military power to be useful. In any case, it was pretty late game, and I had a fair number of automated fleets running around doing raids against my enemy as they saw fit. My allies, however, were paralyzed. Their fleets were stuck in interstellar space, constantly changing their intended destination as the attacks by my automated fleets came and went.
This went on for years. A fleet of mine would attack some remote mining station, their fleet would set in a course to help, but the mining station would be destroyed before their fleet could even engage warp. So my fleet went on its merry way, and their fleet would choose a new destination, and the cycle would continue.
I can imagine this wouldn't be as much of an issue in the early game when everybody can only afford one or two fleets, but once the galaxy's well developed and my empire has hundreds of ships zipping about, allies seem incapable of making up their minds and end up being totally ineffectual. So I guess the only reason I have to make friends is to prevent them from becoming enemies instead. Sad...