There is obviously more than one way to skin a cat. Often the best approach is the most efficient, but how do you work out which is the most efficient way of getting form a to b?

I'm currently working on a ajax diary application for a content management system, and I have decided that it is the ajax call which will be most expensive in terms of server load. When the user adds an event to the database, rather than reloading the entire month's data, I have opted to manipulate the DOM with javascript.

This has cost me a lot more in terms of code bloat, but has saved on the ajax call.

But have I waisted my time? There will only likely be one or two end users for this application, and they will probably only each actually use it once or twice a week to add events here and there.

It seems I can either push the majority of the work load on to the PHP scripts and use the client-side language to just make ajax calls, or I can reduce the amount of ajax calls and give the client-side script more work to do. But I don't know which would be better for my application.

Does anyone have any advice or input on how the go about making these decisions.

Many thanks,
Mike