Too much skill or too much time?

Some people have too much time on their hands

Or is it just that they are very skillful. I have to admire this peice it really is incredible. These guys have done some fantastic work.
I am a great fan of the Alien series of films, Sigourney Weaver really made these films for me, there was a kind of barely suppressed terror that was quite palpable - along with a confident - never say die attitude. Fantastic
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