A lot of truth in that yes. Though I think there is some delusion, founded in self-justification by Ange, in the idea that we lost lots of league games in such a pathetic manner because of the EL. We actually generally played strong (if not our strongest teams) in the last 10 matches or so of the league. And even allowing for a few key players missing, we were incredibly poor.
Throw in the fact that we really struggled against our only two decent opponents in the EL (though yes we won, and great that we did), and the "We focused on the EL and were great in it, and the league in no way reflects what Ange would really do in the league" type argument simply doesn't stack up.
We were sliding under Ange for a long time due to poor coaching, poor tactics and an affiliative leadership style