This one has me kind of stumped. Maybe I'm one of these people. What
is the difference between for-each and apply-templates? I have a hard
time even mentally comparing the two.

One function iterates through a node set and the other matches up a
template with a node based on a given context or passed mode. Is that
the right answer, or close to it?

so think XSLT is trivial.  I always ask them to explain the difference
between xsl:for-each and xsl:apply-templates...