This is a bit of revisionist history.I think you've dropped a bit of a bollock with this one, mate.
Against a packed Palace defence Silva absolutely ran the show for 67 minutes. We really missed him against The Shite who packed the defence, we needed someone to get on the ball high up the pitch in tights spaces. Far from not being effective against tight defences, he's actually the best I've ever seen in demanding the ball in tight spaces and opening teams up.
DeBruyne is more effective against teams that play a high line, allow him space to run in to or play an early direct ball. He often struggles against teams that sit deep and don't allow him any space. Whereas Silva is phenomenal in tight spaces and opening up packed defences. I'm bemused as to why you'd pick that out as something he's ineffective at - it's actually the attribute that makes him stand out as so special.
1. Palace didn't park the bus
2. They had a makeshift defense with a winger and backup starting at CB.
Yes, Dave was great, but lets stay on fact.