I never know with these, but for me the main reason for knowing how to pronounce it is so that other orchid collectors/growers know what I'm talking about.
I therefore tend to ask nursary people at shows or just copy what they seem to be saying. I sometimes have to make an attempt at one, then say "not sure how you pronounce it" in the hope they will tell me. The staff at one of my favourite nursaries tend to be very polite and won't correct me as long as they know what I mean, so I often have to ask for their pronunciation.
Basically I don't really mind if what they tell me is not stricktly right, as long as it matches what people in the UK (those I'm likely to meet at shows) would understand. After all in living languages such as English the pronunciations differ all over the world and it doesn't matter as long as we all understand each other
And of course here on OB it doesn't matter how we hear the word in our head, as long as we spell it right so others know what we are 'talking about'.
Anyway, that's just me
