Yap I'm curious too. If its a bad case of fungus, will it 'eat' into the coatings on the lens elements? And if can thoroughly be cleaned, will it scrap off the coatings too?
just curious, won't the fungus "eat" into the glass?
the fungus doesn't eat into the glass itself, but the material used to coat the lenses. if i'm not wrong they used to use organic compounds to coat the lens, that's why susceptible to fungus. BUT i don't know what they use to coat lenses now. :dunno:
the fungus will destroy the coating - even if it doesn't 'eat' the coating, removing some of it will make your coating uneven, even after cleaning. may not destroy the lens totally, but may affect the resilience to flare, etc, especially if the lens coating was instrumental in the design of the lens.
in short, prevention is better than cure, so store your equipment properly. as for those infected lens, if you feel that it's worthwhile then go ahead and remove the fungus. personally i think that fungus-infected-and-removed lenses won't suffer that much in terms of acuity.