It's just really hard, as an English speaker, to distinguish and produce the required contrast between aspirated and unaspirated stops.
It really is -- and the video does a good job of highlighting those difficulties. I know that many teachers will mention the fact that this was the more nearly correct pronunciation of Attic, but will discard it on the first day in favor of φθχ fricatives. I like the idea, but it is difficult. Attempts to adopt the older pronunciation lead me to the expected awkwardness and errors, mostly over-doing the aspiration to provide a contrast with the unaspirated (a common mistake, as he says).
That is a good chart, thank you for sharing!
Regarding vowels: as I am looking at his chart, although I am consistent, I'd be guilty of the dreaded "anachronistic combinations of phonemes." Is it too sloppy to say that if it was used before the common era it is fair game? Some town could probably be found using that mix.
It's an interesting thought experiment to consider how "evolved" Epicurus's pronunciation was toward fricativization and other features
Exactly, I think all we can say of the Greek used in the garden is that it was somewhere in the evolution -- even possibly including features more associated with later dates.
I published a little Tolkien project a while ago
I am interested, but sincerely ignorant of Tolkien (beyond the fact he is the author of The Lord of the Rings). I just did a quick wikipedia read however - interesting stuff! Is the script of Tengwar actually printed in the books and legible?