The resident evil in CHC--let's be reasonable.
Many French growers are wary of Sanderianum's somewhat fuzzy "science" and "final" pronouncements.
I wholly support Rick's claim but that's only my personal opinion. In any case, there can be no mysterious physical or chemical reason why CHC should be "essentially" bad for orchids. If you buy it from a reputable source, if you wash it and treat it properly (see Antec's website), if you check its conductivity (give or take 60 microsiemens), if you mix it with a neutral cultural medium (e.g. charcoal, sponge-rock, etc.), if you check it regularly for ph, how on earth could it possibly become the evil thing some people imagine it to be ? Of course if you buy CHC with a salt contents which blocks your conductivity meter (this has happened to me) and use it straight out of the bag, problems shall occur but that's only fair.
It is also true that CHC will decompose in time depending on original quality, temperature, and humidity (2 years in my conditions). The CHC particles will form a kind of mud at the bottom of the pot with charcoal and sponge-rock particles--this is bad for the roots especially if you tend to overwater.
The same heated debate has been going on since the 19th C. Every single medium that works for you is THE ideal medium but it would be wrong to apply the same rules to all circumstances and all paphs (I suspect brachys dislike CHC but I don't grow any since they are all die on me).
You'll find that bark is equally difficult to apply to all cases. Bark pellets are lethal to my plants in my conditions and chunks are very difficult to find nowadays. I have never found a bark mix which works in my conditions.
I'd be very curious to know if anyone other than the interested party has ever used Lance Birk's "Pretty Good Mix" (8 parts medium grade fir bark, 2 parts chopped moss, 1 part 16 mesh silica or river sand). For obvious reasons a 16 mesh sifter is not available in France and I keep forgetting to buy one whenever I go to the States. I am sorely tempted to experiment with this mix. Feedback please ?
Happy growing
F.
