I love the show! I have been watching it since the earliest of episodes, but only in the last 2 months have I gotten my roommate to watch it. She loves the explosions and just like you, adores the look on Adam’s face. = )
We are both engineers and craftspeople too… so it doesn’t hurt that they have cool tools in their shop to work with either! In fact, the show I catch her watching most often is American Chopper, since they have a sweet tool shop! 
Modern Marvels is actually a History Channel show. And the battlefield guy is actually Canadian. 
The US has an American host, whilst the first season released in Australia on SBS (as opposed to discovery) had Matt Shirvington narrating (poorly too), this was due to the fact that Beyond Tomorrow productions wanted to use scenes from it in there new Beyond 2000 style show.
The second season showing on Australian TV actually has the Yank host back, so all is good.
Maybe you caught a bit of our Australian episodes?
I stand corrected - thanks to orthopedic shoes!
Nah, seriously, my bad. Sometimes it’s hard to keep all those channels apart: Discovery, Discovery Times, Discovery Health, Discovery Kids, Discovery HD, The Military Channel (which I still think of under its former name “Discovery Wings”), The History Channel International and the plain ol’ History Channel.
As for the host’s Canadian-ness… well, if they don’t speak with the stereotypical Canadian accent, I can’t tell!