CSS Hidden DIVs - not collapsable content. Amber light?

[Bio-RadAbs]

I'm in the planning stage of a new ecommerce page. To reduce duplication issues, my page will be static with 20% of the page compiled of dynamic fields.

So when a user selects a size, or color, the dynamic fields are the only ones that change as the rest of the content is the same. I can keep a static URL and not worry about duplication issues. Focus can be on strengthening this single URL with rich schema, reviews, and backlinks.

We're going to cache a default page so for crawlers, the dynamic field doesn't appear empty. My developer said they can cache the page with all the variants of the dynamic fields, and use hidden DIVs to hide them from the user.

This way, the load speed can be high, and search engines might crawl those keywords too.  I'm thinking about and going.."wait a minute, that's a good idea..but would a search engine think I am hidding content and give me a penalty?".  The hidden content is relevant to the page and it only appears according to the drop down to make the user experience more "friendly".

What do you think? Use hidden DIV or use javascript to not allow bots to crawl the hidden data at all?

[MikeRoberts]

If its relevant, done with usability in mind, and is not deceptive then it should be fine.

Here's a related Article from Search Engine Roundtable with Matt Cutts video:

http://www.seroundtable.com/google-hiding-content-17136.html