Interesting thread... too bad I didn't see it before, been busy elsewhere. I have an idea that can help.
the objections to a dynamic system are logistic; the folks that manage the servers want to have a process where they take a tarball from A, copy it to B, untar it and walk away. The same process means that responsible people will be making sure the site goes through QA before being deployed to live, that writers won't be *capable* of breaking the live site, and nor will anyone on the outside be capable of hacking PHP vulnerabilities, throwing SQL injection into the db, or anything like that. The server admins don't even want a database on there.
Been there. A time where the admin wanted nothing with DB for our dept.
I developed a CMS under Real Basic and it runned on a MAC (woooo system9, before MacosX), it created the whole site as html static pages out of templates, I think I have a backup somewhere. But you want CROSS platform
Under the same circunstantes I created my first web based CMS that used flat files and created flat, simple out of the box HTML files. The benefit is running from the browser on mac, linux, windows, etc... we had too many limitations and little access to security, this method provided great results: pure html. You can even run the CMS from your computer (with LAMP) so nobody will have access to your site, only to the html pages... the site was created after pressing the magic button "create site". There is still a copy running a site of 5K pages with no problems, the downside is you can't allow interaction like forums... that's something else. Well enough of stories, I have an idea that you can use for your situation.
YOU could choose any CMS you want (and know how to use) and install it on your computer, under LAMP, or Xampp, whatever. The whole site will be on a laptop or X computer, nobody will have acces to that unless you want to, you can allow others to edit and manage the site inside your network, no webserver or admin needed.
THEN it comes the magic, you could use some offline browser-downloader that will take the complete site and convert it to html. Then you can zip it and upload the files to the server, it will be a simple matter of unzipping the files and you are done.
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There was a time when one admin knew nothing about wordpress and he was asked to migrate a site from a comercial average server to their solaris customized one... the site was static (it wasn't going to be modified again) so, I suggested the same, an offline browser... it created the offline pages in a click so then we uploaded a zip file, it was very simple, we did it right before lunch.
PS. BTW I had a BETA developing environment like that (sites hosted on a computer) using SLAX, it was a custom install on a CD that I could copy to start from scratch beta testing a new website... old times.