Installing 11.2.0.2.2 - Prerequisites

I have, in the past, installed 11.2.0.3.2 on top of 11.2.0.3.0.

The patch was installed successfully. Now I went to check 11.2.0.3.3. I noticed that it mentions that 11.2.0.3.2 and 11.2.0.3.1 are prerequisites. I was surpised to find out that 11.2.0.3.2 has as prerequisite the 11.2.0.3.1. However opatch gave no warning and everything was fine.

My question: Is it required to install 11.2.0.3.1 before 11.2.0.3.2 although opatch does not require it?