[jauco]

This would be HTR (Handwritten Text Recognition) not OCR and HTR is a lot harder than OCR especially for modern scripts (i.e. student's scrawls). And at every error the reviewer now needs to check if it was due to an error in the code or due to a bad HTR somewhere in the code.

I'd say compared to just typing the code on a disconnected computer: Not worth it.

[DonHopkins]

And then you can grade them on important syntactic issues that really matter, like tabs -vs- spaces.