Grading your own essays

It seems like if you can manage to score a 70%, maybe even a 65%, on the essay section you will pass the exam. Which brings me to the issue of how to grade myself when my answers are somewhat correct. Any tips out there on how to grade your own essays?

Example - a previous CFA exam has a command word EXPLAIN in a question on an option strategy. My answer matched very closely to the CFAI answer, but I did not state the strike and option price in my answer, though my explanation and rational matched.

Do I get 2/3 points for this because I left out that detail from my answer?? Do I get 3/3 because the question only asks to explain, and the extra info is just part of the CFA’s rediculously long model answers?

Any other thoughts on grading your own asnwers?