YAML plugin wierd behaviours

I'm working on plugin which using/depends on YAML plugin. I noticed several wierd behaviours of this plugin:

• On YAMLSequence like this:

- !some.fully.qualified.java.class
     property: foo value
     someOtherProperty: another foo value

     getChildren() returns array of YAMLKeyValues with 2 elements, but getFirstChild() returns PsiElement with text "-". IMHO it is wierd behavoiur - if I ask for first child I rather expect first element of getChildren() - why this works in this way?

• for this example:

    firstProperty:
        - foo value
    secondProperty:
        - foo value

• Not every PsiElement in YAML is visited in annotating - I've noticed that com.intellij.lang.annotation.Annotator#annotate is called by com.intellij.codeInsight.daemon.impl.DefaultHighlightVisitor for every element and its children, but for previous example YAMLKeyValue for firstProperty is ommited (only compound value is visited) - why?