It would be nice if there was some control to ensure that certain initializations occurred before or after others.
A canonical example is a mixin that adds a confirmation dialog to a link; that event handler for the dialog must come FIRST before any other event handlers for the click event of the link. Since Prototype doesn't seem to provide a way to establish that ordering, Tapestry needs to.
RenderSupport.addInit() needs new overrides (or perhaps a new method, addScheduledInit()) where a prioritization is added; the priority is a number; all initializations for a particular priority level occur before initializations for a numerically higher level. The default priority should be some reasonable number (0, 100, 1000 ... but fixed) to make it easier to say "before" or "after" ... much as the CSS z-order property is used.