In reply to ice.solo: Not just different, but rather more substantial forces involved, anyone who's tensioned a slack line against a seemingly secure object (say a lamp-post), or equalized gear for an anchor using too short a sling (and lived to tell the tale) will have first hand experience of this...
This explains quite well:
http://www.chetwynd.info/other/anchors.htm
According to the formulas with an 80kg person in the centre of the traverse, rope straight between the two anchors and minimal rope/cable stretch the anchors would be experiencing in the region of 1130kg (11.1kn) each, and the rope/cable would be experiencing double that... 22-26kn is the kind of breaking strains I found by doing a straw poll of several brands of (10.5mm) static rope*, so you'd have a very small to totally negligible safety margin.
*with 12mm things get a little better with upto 36kn braking strains available, which may be all right, but it's a comparatively specialist product.