[eval] (itself properly seen as a specialization of [uplevel]) is a powerful [Tcl] [command].
Beginning programmers often regard it rather magically, though, and are susceptible to
bad habits in its use.  Let's straighten those out here:

First, dense eval-ing often is a symptom of misunderstanding, generally of the "working
too hard" variety.  Also, eval has security implications [[explain]], so it's appropriate systematically 
to analyze each instance of an eval in any particular application, and explicitly review that
they're all "material".

...