Taka said:
If the clause is, as you teachers say, for all lectures mentioned, I don't understand why the word "even" is there in "even in the lecture hall"...
Lectures on videotape, on audiotape and--if delivered form detailed, antique notes--even in the lecture hall,....
Lectures on videotape (A), on audiotape (B) and even in the lecture halls (C).
'even' =
not just recorded on tape, but also live in person
Lectures on videotape, on audiotape--
if delivered from detailed, antique notes and not improvised to some extent--
The underlined portion refers to 'Lectures on videotape, on audiotape'. It does not refer to '[lectures] in the lecture hall' because those lectures are to some extent improvised.
In short,
"Lectures on videotape (A), on audiotape (B)
--if delivered from detailed, antique notes--and even in the lecture halls (C)."
(A), (B) and (C) form the sentence proper. 'even' means, not only that but this, too. The underlined portion is not part of the sentence proper. It's added information which functions as an after thought. It modifies (A) and (B), but not (C). Since the dashes (--...--) represent an after thought and (C) is not mentioned before the after thought, (C) cannot be included in the after thought.
That is the writer's intended meaning. But, the reader's interpretation is based on what s/he has just read and what s/he knows about lectures: that it is possible that
all lecture notes can be delivered from detailed, antique notes.
All the best,