>increasing KW, maybe that is the reason.
At .co.uk the listings have now return to roughly their originally positions, at .com significant gains have been made.
This is what *could* be happening.
The changes I made to the site were only to the text based hyperlink menu, introducing the root theme keywords into many of the links.
On the pages that were targeted at these root theme words this had the effect of increasing keyword density.
At .com this resulted in the listing for the main targeted keyword phrase dropping from 43 to un-findable. Two update cycles later the page now ranks at 21.
My guess is that initially the alterations were seen as keyword spamming by AV, until such time as the keywords were accepted as part of the sites theme, and an allowance/adjustment made for pages targeted *directly* at the theme keywords.
This could also explain the drop reported by some when pages are resubmitted, leading to, in my opinion, the false view that older pages do better.