I think that comes from all of us who work with SQL know we don't and can't know it all. I know the core of SQL and can setup just about any version without thinking abut it. I can also do programming in T-SQL and debug it as well. But I also know that I haven't used every keyword of T-SQL. My new job has some pre-done scripts we use. The one script uses UNPIVOT. I had never seen it before now.

I've barely touched SSIS and don't know SSRS at all. So as soon as you feel high & mighty and all knowing. Go to one of those gatherings and you will not retain that feeling long.