Johnnie Walker Green

[Son-o'-the-Sod(?)]

[First, my apologies if this has already been covered elsewhere in the "Whisky Blends" threads]:

I'm enjoying some JW Green and pondering two questions:

1) the 15-year age statement: I assume this means the spirit(s) are aged fifteen years AFTER being blended; there are the four constituent malts listed on the packaging (as well as others not named) and I would further surmise that it's younger ages of these that go into the blend;

2) of the four identified malts (Caol Ila, Cragganmore, Linkwood and Talisker), which one (if any) is predominant? Seems that Cragganmore might be more forward, and both it and Linkwood are distilled more for blending than as single malts.

Any ideas, experts? (-Dale?)