Steve;
"Buchan, Child, Sharp, MacColl were not gods, not perfect"
No, they were not - but both of them have been dead for some time and both made considerable contributions to our understanding and enjoyment of traditional song.
There is certainly nothing wrong with critically evaluating their work, but repeatedly debunking it and treating it as just good for a laugh without additional information seems, to me at least, little more than stoning corpses.
As far as John O Hazelgreen is concerned, I've never found it a particularly inspiring ballad, but there is no evidence that the 'dream' references (hardly sequences) provide proof that they are "rather typical of the interference he makes in most of his versions of ballads". The 'love through dream' motif is a common one in balladry and folklore (Stith Thomson T11.3), and while it is not used particularly well here, like many of the accusations thrown at the late Peter Buchan, there is no evidence whatever that they were his own creations.
Bucan writes of the ballad "This appears to be the original ballad of the name"; it seems to be that accusing him of faking it is little better than saying he was a liar. Without substanting the accusation, it is neither fair nor productive.
I often think that Buchan got the flak that he did because his collectition deflated many pre/misconceptions about balladry, and is still doing so in some quarters.
Jim Carroll