Because, I see several scenarios:
#1- A Parallel storyline-
The Unfettered Healer dresses Covenant in white samite. Later Covenant's clothing is stained green from Moss. When Covenant awakens in our world he is wearing a white hospital robe with green spots on it.
Linden's clothing stained by the grass, and the Mahdoubt's mention of the significance of clothing especially to Linden.
Are we being told that Linden may yet survive in our world ? If this be true, would that tie the Mahdoubt to the Unfettered Healer in a repeated character kind of way ( associated with healing?) Maybe that's a little too far fetched, but just a thought.
#2- Linden's clothing has been marked with the necessary Runes needed for the NSoL and the Mahdoubt is trying to convey that to her without coming out and just saying it, considering SRD's choice of description for the stains. This to me, doesn't seem so far fetched.
#3- I've drunken a bad Diet Coke and am just talking nonsense

...I dunno, but it's always easy it seems to tie things together with the TCoTC....I guess that's how SRD has concieved 10 books for the series.LOL
any body else see what I am ? or should I just shut up ?