Hmm..I think that like others I have a problem with the notion of the words being Englished.. It's quite evident that Hamish Henderson took very great care in choosing the words and phrases in English and in Scots to make the impression and convey the emotion he wanted.
I think that it's a song that doesn't Anglicise easily or well. A lot of Scots songs can be transformed fairly easily - change "weel" to "well", "hame" to "home" and so on... I don't think this one is as douce...
To transform this one, you really have to set about it with a hammer, as Keith (in my opinion) has done. It ends up a different song, (which might be OK), but it's still a different song...
Cheers
Steven