A direct comparison between constrained and unconstrained problems is misleading when the constrained problem must perform additional tasks.

“mathematically it's not harder. But of course this is kind of it's a wrong comparison, because you're comparing a constrained problem versus an unconstrained problem. The constrained problem of course is harder because it needs to do more things. So it's so the actual comparison would be something like I have an unconstrained problem and I have a constrained problem which is both of which are really really difficult,”