I suggested truncate so you could start with an empty table before importing without having to drop and create. If you are dropping and creating the table, you are effectively truncating.
"Use Array DML" has nothing to do with truncating though. That will cause each insert statement to insert a batch of rows, rather than one at a time. It really speeds things along. I would guess that your 10 minute import would drop down to 30 seconds or less.