Tweak explanation

Signed-off-by: David A. Wheeler <dwheeler@dwheeler.com>

docs/labs/create_checker.md

@@ -767,12 +767,14 @@ However, cheating is fundamentally a lazy approach, and we take steps to
 address this.
 The "give up" button has a timer, so people can't load the page and
 *immediately* give up to see the answer.
-When a lab is completed, that is clearly indicated, and we also add
-a random unique value to the bottom of the completed lab.
-That random value also includes `(GA)` if the learner gave up in this session.
-If two learners have the same random value, then one copied directly
-from the other.
-This doesn't prevent all cheating, but it does provide a way to detect
+When a lab is completed, that is clearly indicated at the bottom.
+In English this stamp has the word "Completed" at the bottom.
+After that, it has a datetime of the completion time, followed
+by a random unique value (a UUID).
+That is followed by `(GA)` if the learner gave up in this session.
+If two learners have the same random value, then a single lab
+session being claimed by more than one learner (thus, there was cheating).
+This doesn't detect all cheating, but it does provide a way to detect
 some kinds of cheating.
 
 ## Potential future directions