It's far more likely you'll succumb to the temptation to clutter your homepage if you first create a full-size design, rather than designing the mobile homepage first.
Look at how the gaze plot and heatmap from Feng-GUI shows the human eye having too many focus spots on the regular home page ... and this
is Amazon we're talking about, the retailer everyone looks to for leadership in
usability and conversion rate optimization.
Gabriel Goldenberg | Owner of SEO ROI
http://seoroi.com