Yes, Untangle is highly threaded. Which means it needs to be able to process as many threads simultaneously as possible.
The clock speed can be rather low, if it can have multiple threads running at once. Think of each thread in terms of simultaneous AV scans.
What's faster? Lining up all those AV scans on 1 super proc? Or queuing them up in multiple slower lines? The latter is the reason why we have multi-core, and Untangle is one of the few products that gets an extreme boost.
And the fact that it has a SQL server in it... only adds more to this idea.