storePath() might cause url aliases in a "different subtree" to be reparented. That means, if you say have some custom url aliases elsewhere in the tree, those might be updated and put underneath the url element, for which the custom alias points to. Here tree means the nice url paths, not the content tree.

In the worst case, this might lead to a database error, namely a duplicate key entry.

Example:

\
|-- TheRealFolder
|   `-- MyNode
`-- VirtualPath (Virtual path element, a nop:)
    `-- AliasToTheRealFolder (Alias to TheRealFolder)
        `-- AliasToMyNode (Alias to MyNode)

When publishing a new version of TheRealFolder, you don't want that to change the placement of AliasToMyNode, to become a sibling of MyNode.