Aware of that Ian, the thread/hair I have/had has always been a flow issue (it's pretty much my way of seeing where flow is bad in the tank, generally because somethings sucker has fallen off), except when my CO2 cylinder ran out when I was away for a few days. The trouble is the moss grows well, slows the flow down, and grows hair algae unless it's plastered hard to the wood, buffeting it hard seems to be my best way of clearing it, but I mean really hard. I think it can create it's own little cocoon of low flow/CO2 once the two get properly mixed up.
I guess I'll have to go down the same route and start back from the clean bits, was just wondering if he'd succeeded in clearing the moss.