This 304 thing is new to me and sounds interesting. Thanks.
I assume it has nothing to do with the date-last-modified-entry on harddrive? I use a lot of scripting and even my .html-pages are parsed as php-files. So it wouldn't make sense to deliver a 304 according to datelastmodified if some of the scripts involved have undergone changes meanwhile. And I think I'm not the only one, who does so.
I have a managed server on a well-established larger hosting-company and I assume they have implemented their own cache-system in order to reduce processor capacities, thereby delivering a 304 by default whereever appropriate. I might try to find out about this exactly via mail, but maybe you know, how this is generally handled?
I took a closer look at the figures:
The overall traffic in megabytes amounts to 2-2,5% for the figures given in GWT. As for the number of pageviews googlebot is crawling approximetely one third of my pages every day, which amounts to 5% of all pageviews. I think the difference as compared to traffic volume results from the fact that googlebot does not request images?
The average load-speed lies around 1200 milliseconds and the GWT specifies this as complete pageload-time, not server response-time. I think I can live with that.
I still use a table-based design, but with a php-flush() command after the header-table, which thus loads very quickly. Due to a varying amount of db-requests (up to 40 products per page), some pages (tables!) of course take a bit longer to load but we never had any visitor-complaints concerning load-speed whatsoever.
> I've found that Adwords QS imrpoves tremendously as load speed goes up, and I'm beginning to suspect that the same is a factor in organic ranking.
This is what I also suspect and it would be very interesting to get some details on this.
> regional average plus 3 seconds.
I think I'm far better than that.
I hope the figures I gave might help others to narrow down things a bit. So far two questions remain for me
1) what the hell is "regional average"?
2) Since when does GWT show these graphics? I think the last time I visited that page before was in autumn last year.