This a recovery test. I dropped all control files and all datafiles while the db is up and running. Then, I use rman to do the following restore and recovery. As fas as I know, as long as you have all archived logs and online redo logs, you can recover and open the database without "resetlogs." Why does this one require me to "resetlogs"?
allocate channel tape1 type 'sbt_tape';
allocate channel tape2 type 'sbt_tape';
alter database mount;
sql "ALTER DATABASE OPEN";
release channel tape1;
release channel tape2;