These occasional breakaway happen to every top team. The only major difference was that there keepers made saves at a higher rate than ours. Put another way, as shitty as most thought our CBs and FBs were, they gave up chances at the same rate as Chelsea and United and slightly less than Tothenham. They were far superior to Liverpool and Arsenal. But Chelsea and United's keepers were just significantly better than ours.
For all intent and purpose if you exclude goalkeeper performance, only Tottenham played better defence in the league.
So its either the whole league barring Tothenham is shit, or (more rationally) our CBs are not as shit as advertised. I'm going to go with the latter.
Any position can be strengthened. I don't want to pretend CB can't. But nothing suggests its a particular problem. We have a great on Komps, a top 5 defender in Ota, a developing Stones and a quite capable Kolarov. We are spoilt for options at CH.