This is such a difficult thing for students to believe. But I try to say this in some variation every day to my students.
Grace nails the sentiment here.
points out diff btwn "show your work" as window into S thinking vs as backwards engineering what the teacher wants me to write— grace a chen (@graceachen) November 3, 2016
Once students begin to believe that the way they see something is the currency, then our job is to simply help them refine their communication so their audience can understand them. Only then does the syntax of mathematics matter.
"Help me understand you."
"Help me see what you see."
These are the things we should say more often.