Chris Hartjes has posted a mini-tutorial on working with HABTM (Has And Belongs To Many) relationships in a CakePHP applications alongside pagination.

There are usually lots of Has And Belongs To Many relationship questions on the CakePHP mailing list. Since I am stupid about this stuff, I sought out Nate Abele and bugged him via IM until he agreed to give me an example of how to do this.

He includes both the how and the why, explaining that merging the parameters allows the script to apply the HABTM connections as well as limiting the results for each page.