1. The RSS and ATOM feeds only show the most recent 15 comments/articles I think (haven't looked at RSS code in a long, long time.) This is/was the recommendation when I implemented it, and I think WordPress served up the most recent 15 so I followed suit. Also, I'm sure there are bandwidth considerations. Why transmit all 200 comments/articles on a site every time -- just send the most recent stuff.
2. Note the timestamp Time Zone: GMT. RSS feeds are (I vaguely remember this requirement but I may be wrong) supposed to have GMT timestamps as a universal point of reference for everyone worldwide. So 7 hours off seems just about right -- as long as you see GMT. The timestamps should show correctly on your site because if you look at your wb.xml file, the timestamps should show your server's timezone offset, ie -07:00.
Sincerely,
Carl
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