"#name" does seem to be documented:
asset():
Name - The name of the asset, as in the asset list or the [Asset] selector. An empty string "" creates a dummy asset, a name beginning with '#' prevents loading price history.
Asset Lists:
The asset is ignored when the name begins with a hash character "#".
This also requires a clarification:
If several symbols are used and one of them is blank or empty (f.i. "AAPL! !"), the prices of that asset are not downloaded or retrieved from the broker.
(..is it one or several??)
