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You can do so, Good luck for your new lauch. @jimmy cleared at first instance.

Like you mention, the introduction copy on each category page contain naturally placed links down to sub categories and products and should each sub category link back up to the main category page. What we typically recommend is that you concentrate on linking to "on topic" pages. Take a look at what Amazon has done, as their internal link structure has always worked well for them. Each product links to other related products, and products that "others have bought" or viewed.