I'm not trying to justify it, because I simply do not support it, I am merely trying to understand Spalletti's demented logic.
For one, it seems he actually, no joke, does rate Vecino and Valero. He did after all, specifically request him and he wanted Valero back when he was at Roma. That in itself is disgusting, but it is what it is. Moreso, I imagine he thinks that from a simple numerical perspective, 2 midfielders are better than 1 - even if the one is a better player than the other two shitstains combined.
Imagine if we did include Gagliardini at the expense of Vecino and Valero, and he or another midfielder got hurt? It would cause an entire reshuffle of our team considering our lack of options in midfield and LB. Clearly Baldman has no intention of using Dalbert and wants Asamoah as his LB. That's fine. But if a midfielder got hurt, we'd either have to drop Nainggolan deeper into the holding midfield (and I remain unmovably convinced that Spalletti specifically wants Nainggolan at AM), or pull Asamoah from LB to play in midfield. With Vecino and Valero in the squad, even if a midfielder got injured, we'd still have more "options" - even if they're fucking garbage.
Fucked situation really. As ADR said, there's so much to blame to go around. I hate all of them.