She’s in pain, he says something smug and insensitive – ergo, holes in his head.
Woozy’s interpretation may be correct, but I still don’t get the joke.
They’re missing a step: the “holes” that are you sinuses need to get clogged, and there needs to be a change in pressure, then you get the pain. So really, it’s because the holes to the outside are absent (clogged) that you get the pain. So the more holes you have, the better, since they’re less likely to be clogged, so that’s exactly what Arlo has: lots of holes, so the pressure can always be equalized, so no pain.
The joke don’t work.
Arlo has a lot of metaphorical holes, so one would expect some fraction of them to be regularly clogged up. Not a knee-slapper, but it works fine…
Now, I’ve got “Evil woman” stuck in my head.
Is Arlo thinking maybe he doesn’t have sinuses at all?
I thought it was pretty good. Arlo is being his self-deprecating self, is all.
I thought it was that Arlo just found out what sinuses were, and he has now realised he has holes in his head…you think he might be upset (miserable) because of this. Holes in your head don’t sound pleasant.
Comics I Don't Understand 
No, because he does have holes in his head.
She’s in pain, he says something smug and insensitive – ergo, holes in his head.
Woozy’s interpretation may be correct, but I still don’t get the joke.
They’re missing a step: the “holes” that are you sinuses need to get clogged, and there needs to be a change in pressure, then you get the pain. So really, it’s because the holes to the outside are absent (clogged) that you get the pain. So the more holes you have, the better, since they’re less likely to be clogged, so that’s exactly what Arlo has: lots of holes, so the pressure can always be equalized, so no pain.
The joke don’t work.
Arlo has a lot of metaphorical holes, so one would expect some fraction of them to be regularly clogged up. Not a knee-slapper, but it works fine…
Now, I’ve got “Evil woman” stuck in my head.
Is Arlo thinking maybe he doesn’t have sinuses at all?
I thought it was pretty good. Arlo is being his self-deprecating self, is all.
I thought it was that Arlo just found out what sinuses were, and he has now realised he has holes in his head…you think he might be upset (miserable) because of this. Holes in your head don’t sound pleasant.
New category? ‘No, Arlo is not that stupid’