Maybe Reiner has a view.
As if
It´s a fair point, Jim. I think it´s in Hoffnung´s MUSICAL CHAIRS in which there´s a picture titled "Television will establish a new intimacy between performer and listener", accompanied by a drawing of a tubby gent at home tickling the on-screen conductor under his armpits
Of course, the whole medium of opera (and theatre as a whole) - especially in its "commercial" C19th form when box-office receipts had to pay all the bills without a sponsor or patron helping-out - depended on mass audiences, and thus on huge theatres. The idea of being able to count the prima-donna´s eye-lashes in close-up, or check on the manicure of the tenor, is completely new. Acting for the small screen is a completely different can of worms than treading the boards - I´m sure Ron will expand on this, since he´s done both?
I went through a long period of never buying ANY opera dvds - partly because the screen transfers were often poorly done, partly because I prefer the live medium and the "record-collector fetish" for "benchmark" performances, but also - ehem - because they used to be outrageously expensive. I´ve come full circle as the price has dropped, and my feeling is that if I can see an interestingly-looking production from somewhere else in the world I´d never get to in person - and only pay 10-15 quid - then it´s worthwhile. I´d shrink from some of the 30-40-pound box sets, however, simply because it´s very, very unlikely I would ever watch anything much more than once.
As you say, you´d have to be quite convinced before lashing-out for a pricey opera dvd. I recently bought the Boulez/Chereau HOUSE OF THE DEAD, and I´m afraid I don´t like the production at all (it fails on so many levels). However, as a musical performance it´s worthwhile, and I´ve found I´ve listened to the music alone without the screen presentation.