Either will work, but keep in mind that 'Zephirine Drouhin' is not a modern climber, and will likely grow larger than most standard trellises. I think doing the figure-8s is a way of trying to get the most out of a rose that produces fewer but longer climbing canes, whereas fanning out horizontally works for roses with more climbing canes. It's all about getting what you have to cover the intended surface. And whenever a cane is bent to between 45 degrees and horizontal, it will break into more lateral flowering shoots.
:-)
~Christopher
Q
Climbing roses
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