I like and that's quite the interesting twist on the troll incident. Of course Matt carries something like that, it's -standard issue- for boys with sufficient maturity in farming/hunting country but I daresay it'd be rare in muggle Britain let alone wizarding Britain (where doing things -without- magic seems to be the greatest blasphemy). Having said that, do both Matt and Harry have leathermen, multi-purpose tools, too? I can see that being useful down the line.
The howlers from home are a hilarious number and I wonder if Minerva's sent a few back to James, Lily, Sirius, and Lupin?
Author's response
Lily and Lupin weren't in on the Howler. Lupin still lives in Britain. The third one in on the howler was Mr. Robertson.