Non-contiguous selections in 10.4 Cocoa apps

macosxhints - Create non-contiguous selections in Cocoa apps:

Discontinuous selections were introduced in 10.4 ('Tiger'). Hold alt and drag for a 'rectangular' selection (only truly rectangular with monospace fonts); Hold command and drag for discontinious selections.

Select then command click on items in selection may also make the selection discontinuous, but the comments are confusion. Need to test it myself.