It should work, just pass in variables. However, one thing I noticed is that you should not query for the passed in variables in ad_page_contract of the included page. This will set the variable to default, throw an error, or it silently uses a pre-existent value. This means, that if foo is in the original page, you may want pass foo2 with the include tag and use:
if {[info exists foo2]} {set foo foo2} (or change what ever property you like)
You could also put @foo2@ straight in the adp file, but this will throw an error whenever the original templated page is not called from within the include.
