There are three problems with the implementation of TINY_TREE_CONDENSED:
When a text node is created that shares the string storage with another text node, the "next" pointer in the tree is not updated correctly, which may cause a subsequent ArrayIndexOutOfBoundsException when navigating the tree.
The code does not correctly handle the situation where two adjacent text nodes are written to the tree. This will not happen for a tree built by parsing lexical XML, but it can happen when constructing a temporary tree.
The code does not always detect when two text nodes have the same value (this is a consequence of the fact that CharSequence.equals() delivers unpredictable results when different implementations of CharSequence are used). This bug causes no harm, but fixing it exposes the other two bugs making them more likely to occur.
A patch is being raised which abandons the attempt to common-up storage for text nodes. The effect is that TINY_TREE_CONDENSED only affects the space used by attribute nodes (which are unaffected by these problems). The facility will be reinstated in the next development release.