Because it's a minimal ajax library.
Yes, I know there are many Ajax libraries available, but they are too complex and I need just the basic part. Also add those libraries in each plugin would be a redundanct code situation.
Yes, there is an Ajax library in WP, but I need an extra element it hasn't, and hacking the WP Ajax library wasn't an user friendly situation in order to make a plugin easy to install by common users. A common user wants to install, not to hack.
Yes you can. Take a look at the readme file in /doc/ directory, and see the example. Remember this is an Ajax library, so it has the same limits other Ajax libraries do have.




