Can someone point to me or explain if this is true, you must not use plain any plain HTML tags in JSF or JSF libraries like RichFaces? 

We're using JSF 1.2, RichFaces 3.3.3 and Facelets on JBOSS server.

Someone said to me that we must use only `<rich:>` or `<f:>` or `<a4j:>` and the components they offer. Reason being that the JSF component tree would break and you may have unwanted behaviour. Or lose the JSF tree structure at some point and the functionality associated with it.

I was trying to use a plain `<h1>` tag and was told to not use it and use a `<a4j:outputPanel>` instead (which renders as a `<div>`) and style it to look like a heading.

I'm having a hard time believing this.