Youre right. My grumpy side was out strong this morning, and it was too much to lump together. We know how much the earliest days of musical theatre borrowed from operetta, not to mention Gilbert & Sullivan, etc.
As for Mr. Terfel --
Aside from the acting, which I really was unconvinced by -- as is crucial for Sweeney -- his casting illustrates something else for me.
When SWEENEY TODD or WEST SIDE STORY are sung by true opera stars, it exposes the limits of what the composers wove into the roles. It's like hearing a country tune for a fiddle played on a Stradivarius violin. When you hear a voice this big, with that much dexterity, it only makes me wish that the composer had written something harder and more expansive.
It's like watching Olympic-level skaters skate an entire program with nothing but single axels.