Lukas Smith recently posted about issues he's been coming across with the "KISS" mentality (and code) that the Zend Framework implements, specifically for the Zend_Feed component.
Now that I am actually using the Zend Framework on my first project, hitting bugs/limitations in Zend_Feed and therefore looking at the code, I must say I am seeing feature duplication with internal PHP features that does not quite fit in with the KISS principle.
He points out a few things that illustrate his point - the use of Zend_Http_Client instead of a strea context, passing XML contents into loadXML instead of just load. As a replacement, he's considered a Feed component from the eZ components system, but it hasn't been released (officially) yet. So, as an alternative, he's come up with a patch to fix a few things in the Zend_Feed component to make it a bit more KISS-friendly.