I released my first module well before I 'mastered' the toolset (if indeed that's possible, as it often feels like *it* is the master of *me*). It certainly isn't my best work, but then again it was quite playable and didn't suck too badly, which is all you can really ask for in a free download.
There's no need to start with an enormous campaign full of custom content and hideously complex scripting. There's much to be said for quick and simple modules. Sometimes you just don't have enough time to commit to lengthy campaigns. I'm always on the lookout for good short modules to distract me for an hour or two.
I created Shaar Moan specifically because there was a complaint in a forum post about people spending years developing large campaigns, resulting in releases being few and far between. I threw that module together in a couple of months.
It wasn't until I was highly proficient with the toolset that I released something larger (Isle of Shrines), which took a couple of years to complete. I've been working on my current (even bigger) project for a couple of years now too.
If you start small and work your way up to a more complex project you not only learn the toolset through practical experience (which beats any tutorial), but the community will get to experience your efforts sooner and more frequently. Everyone wins.