Just posting to balance out the fray of re-entry experiences.
A couple of days I did my first re-entry into BKK since getting my soft power DTV in March. Still have about a month of classes left. I brought printouts of the visa, recent 90-day report, and credentials from the gym. Line moved fast. I presented just my passport first, and the officer asked for nothing else. No additional questions or commentary, just stamped, and waved through.