The offense has looked great lately. You can point to the poor defensive teams we faced if you want, but we are scoring with ease with crisp ball movement, attacking the basket, and hitting open shots. That should happen against any team when those things occur.
The defensive numbers don't look great, but they held nice leads and let them slide. If the games were close they could have locked down IMO. I personally believe JO is a better defender than Perk (except against D12). The only question is will he be healthy and learn the system Perk had years to learn alongside KG.
If the C's can go into the playoffs with this strong, versatile bench AND be able to close out games with Rondo/Ray/Paul/KG/JO, that will be the lockdown defense to hold leads (and extend them).