When auto encryption is configured on a client, we generate a batched bulk write command using the OP_QUERY command code path, then chop off the OP_QUERY message header, then decode the encoded batched command, and finally we send that command to the server (re-encoding).

This decoding and re-encoding is not so bad because we use RawBSONDocument to avoid decoding/encoding the documents to insert/update/delete but we can improve this further. One improvement would be to use PYTHON-1917 to execute the encoded command directly.