The Annual Argument

Ben and I got our Christmas tree yesterday and ended up having the same discussion we have every year:

Bronwen walking over to the car: Have you tied the tree to the roof yet?
Ben: No, I'm just going to hold it.
Bronwen: Hold it to the roof from inside the car?
Ben: Yes.
Bronwen: You are going to hold the tree?
Ben: Yes.
Bronwen: With one hand?
Ben: Yes.
Bronwen: Out the WINdow?
Ben: YES.
Bronwen: while we DRIVE?
Ben: yes.
Bronwen: 35 mph and around corners?
Ben: It will be FINE.
Bronwen: Ben---

The conversation goes on and on like this until segueing into exasperation. How would you explain to the person behind you whose windshield your tree just smashed that it wasn't tied down because you'd decided "just to hold it"? Unlike most years when I march back into the tree lot, muttering to myself as I unravel 20 feet of string, and march back to the car with the tangled mess of it, this year I gave up early. I couldn't bear the ridiculousness of the argument -- or the fact that, once again, we were having it.
Ben: "This is going to work fine -- I'll just tie net around the tree to the roof rack."
(tie the net to one side of the roof rack so that worst case scenario -- hopefully -- the tree just rolls off the roof and hangs along the side of the car hiding us from anyone who thought a Christmas tree was tumbling off the roof and about to hit them).