I’m reminded of Wilfred Owen’s Anthem For Doomed Youth (1917, when it was still a custom to lower window blinds on a death in the family):
What candles may be held to speed them all?
Not in the hands of boys, but in their eyes
Shall shine the holy glimmers of good-byes.
The pallor of girls’ brows shall be their pall;
Their flowers the tenderness of patient minds,
And each slow dusk a drawing-down of blinds.
Until whomever Jerry Garcia is establishes more linguistic authority than the Oxford English Dictionary we’ll consider their view nowt but an ambit claim.
1.b.
to draw the curtain: (a) To draw it back or aside, so as to discover what is behind; (b) to draw it forward in front of an object, so as to cover or conceal it…