Dario,
I'd be curious to know what happens if you comment out that line and tried with this one instead:
set curriculum_bar_p [util_memoize "llength [site_node::get_children -all -filters { package_key "curriculum" } -node_id $subsite_node_id]"]
After you have reloaded the page, with the new code, is it any faster? Fast enough? If so, this change may be considered to be enough, and in which case I'll commit the changes ASAP.
Parenthetically -- The util_memoize call means that you'll have to restart the server for each new curriculum instance that you mount - however, this shouldn't cause any additional problem since curriculum is already (mis)constructed in such a way that you need to restart the server after an instance has been mounted in order to make the user tracking work in the curriculum bar. This "feature" has been documented, at least ...
/Ola
