stevo_ said:
I think its because the HRef is stored within the attribute collection that is inherited from HtmlControl.

InnerText literally just adds a new LiteralControl inside the HRef controls and also adds the content to the viewstate.

Not entirely sure why its doing this, but if its a problem with the AttributeCollection, you can expect it to lose the Title attribute as well, since that is also stored in the base classes AttributeCollection.
stevo_ the problem seems to lie somewhere else because the Title attribute appears after retrieving the Cached control