ContextConfig.webConfig() does the following:

1. Scans for web fragments
> Map<String,WebXml> fragments = processJarsForWebFragments();

This method
a) returns a list of all JAR files, not ignored by jarsToSkip options
b) parses "META-INF/web-fragment.xml" files when they are present

2. Filters and sorts them according to ordering
> orderedFragments = WebXml.orderWebFragments(webXml, fragments, sContext);

3. Uses the ordered set of fragments to look for SCI declarations
> processServletContainerInitializers(orderedFragments);

4. Uses the ordered set of fragments to
- scan them for annotated classes
- merge into main web.xml

5. Uses the original list of web fragments to scan for resources.
> processResourceJARs(resourceJars);


I am saying that parsing of the fragments (step 1-b)) can be skipped when the web application is configured with an empty ordered-fragments element and web.xml validation is turned off (strict servlet compliance is off).

Note that metadata-complete=true alone does not allow to skip that parsing, because we need fragment names to perform the ordering.

It seems that skipping that parsing when validation is on would be a bad idea. We are still using those JARs for resources and thus I think we should validate them.