To Index Categories or not – Curated excerpt V/s Auto-except

WRT: http://wordpress.org/support/topic/plugin-wordpress-seo-by-yoast-to-index-categories-or-not-when-site-or-organized-by-category

Hi Joost.

Using this thread since the relevant topic is closed.

My question: In our case 90% of the archives’ posts have excerpts auto pulled from the post content itself, so can we keep them (category archives) indexed? The excerpts are the first 45 words of the post content, unless curated excerpt is placed by the author.

Looking forward for your insights.

Thanks.
Vivek

http://wordpress.org/extend/plugins/wordpress-seo/