[Sorry I am going off topic here - I will get back on topic in a moment, promise]
Coupons are overdone.
On the other hand, I was searching for some coupon sites the other day to find some usable coupons and noticed there was a dearth of any good quality sites. They all seemed like typical "Give us your email so we can spam you... er.... we mean, send you valuable coupons" type sites.
I think the world could use a really good manufacturers / stores coupon site. One that actually gives out coupons without trying to harvest emails.
Maybe they are out there somewhere. I would love to know about one or two of them. When I started a thread in the Foo forum asking if anybody knew of any good coupon sites, nobody replied.
Back to being on topic:
If I read you correctly, it sounds like you will set up your site so that each individual coupon will have its own page, is that right?
Would it not be better to have pages that are coupons sorted by group, such as: Cereal coupons, produce coupons, coffee coupons, or to set up pages where the coupons are grouped by manufacturer or store?
I think if you had those pages as your main indexed pages with a lot of content on them, and either noindexed the individual coupon pages, or put the individual coupon pages in a directory and robots disallow that directory, that should be fine.
It might be similar to how lots of forums I see operate. They have lots of posts that rank well. Yet they link out to lots of profile pages of forum members that are disallowed via robots.txt (so as to avoid people spamming with profiles). That doesn't seem to hurt the ability of those forum posts to rank well.
The webmaster world forum pages are actually a good example of this.
It's not a perfect analogy, but the similarity is that each of those forum pages that DO rank well will have several links to (member profile) pages that are NOT INDEXED / blocked via robots.txt, and that doesn't seem to hurt the ability of the forums to rank well.
so a coupon CATEGORY page could rank well even if it links out to dozens of individual coupon pages that are noindexed or are disallowed via robots.txt