Both are already important focus cities for U2, it makes sense to base some a/c there. With AF you currently have to go through CDG first to get to anywhere else in Europe, and there is definitely potential for more direct routes from these cities.
This is a direct attack on AF's new basing strategy, but also on Vueling which has started a small base in TLS this year.
Finally something is happenning in French province! The experience in Lyon seems to show that they can live side by side. Although that was pre-lowcost Airfrance...
But if EZY copies AF, in spite of supposedly high labour costs, that means they might be onto something. What is the saying again? Immitation is the most honnest way of praising?