[JonM]

Suboptimal from what perspective? Server processing time & data transfer - maybe, user experience - not necessarily.

Ajax calls aren't by more optimal by definition, it depends on the context.

Agree that worse UX will frustrate users making them less likely to spend time on the site and have less interaction.

For the advertising that is sold on my site, the CPM is determined by the number and quality of Unique Visitors and volume is determined by Page Impressions.

So it's good to have a large number of page impressions, but actually I need to build my audience (UVs) which is more difficult (to a point).