From what I've seen in videos, the challenge doesn't become hitting him with the bugs, but making sure you're in his face while you're trying.
All the Hakumen's I've seen in videos only abuse the barrier at long range, so it makes sense to try to stay in their face before curse is on, so when they are cursed, you still have the advantage of lock-downs and mix ups.
That's probably where the 5-5 comes in, with it being even, in some summaries.