The CSS and JS inefficiencies in the examples are quite common across platforms actually, it is not a xPages thing by itself. Typically it occurs when working with frameworks that componentize UI assets and behaviors. In combination with developers who are not aware of the performance penalty (or lack the time to optimize it), you get the result as seen, a very sub optimal speed.
The very good news is that often with very little effort, you can reach a performance gain of 500% for those websites. Use the tools like Google PageSpeed and Yahoo's Yslow on the site and they will tell you exactly what to do. Most often it is simply a matter of gzipping, combining files, spriting and caching.
I've found that few developers are aware of front-end performance, whilst I once heard that 80% of the time between requesting a page and the user actually seeing it loaded and fully rendered occurs at the front-end, not the back-end (can't remember the source, sorry).
I can't blame those developers. They are asked to be everybody at once: designer, database admin, programmer, security specialist, analist, support engineer. Until two years ago I had no idea either how some simple adjustments can dramatically speed up a website at allmost no cost.
Sorry that I cannot answer your original question as I have no xPages experience. I can tell you though that this is not an xPages specific issue, it is a general front-end engineering issue.
The CSS and JS inefficiencies in the examples are quite common across platforms actually, it is not a xPages thing by itself. Typically it occurs when working with frameworks that componentize UI assets and behaviors. In combination with developers who are not aware of the performance penalty (or lack the time to optimize it), you get the result as seen, a very sub optimal speed.
The very good news is that often with very little effort, you can reach a performance gain of 500% for those websites. Use the tools like Google PageSpeed and Yahoo's Yslow on the site and they will tell you exactly what to do. Most often it is simply a matter of gzipping, combining files, spriting and caching.
I've found that few developers are aware of front-end performance, whilst I once heard that 80% of the time between requesting a page and the user actually seeing it loaded and fully rendered occurs at the front-end, not the back-end (can't remember the source, sorry).
I can't blame those developers. They are asked to be everybody at once: designer, database admin, programmer, security specialist, analist, support engineer. Until two years ago I had no idea either how some simple adjustments can dramatically speed up a website at allmost no cost.
Sorry that I cannot answer your original question as I have no xPages experience. I can tell you though that this is not an xPages specific issue, it is a general front-end engineering issue.