"The condition evaluates false until $left evaluates true. Then the $left condition is ignored, and the condition continues to evaluate true until $right evaluates true, at which point the condition evaluates false, and it goes back to check $left."

Not very precise, and a bit misleading. In the case of "if (2..4)", $left is 2, and $right is 4, both of them always evalutes to true. I know that later you explained that, they were compared to $., and that was right. I suggest you reword this part to make it correct, and agree with other parts of your post.

I think it would be useful to give this example, to explain an interesting situation, which people might run into:

use strict;
use warnings;

open(FILE, "<", "test.dat");
while (<FILE>)
{
    print if 2 .. 4;
}
print "=====\n";
open(FILE, "<", "test.dat");
while (<FILE>)
{
    print if 2 .. 4;
}
====input====
one
two
three
four
five
====output====
two
three
four
=====
[download]

This reminds people the fact that $. is not reset when a file is reopened when no explicit close() called in between.