Just a shout-out to the staff at Tableau and the entire community here, for creating and supporting such an awesome product
I've been using Tableau for just over a year and in that time I've learned a TON from reading and participating in the Support Community and using Tableau on (almost) a daily basis.
My work this week has been especially interesting - I've been working at this site on & off since March, typical Tableau visualisations with a few cool tricks added in where I can and always making sure it's easy for the client to add new data and not have to do a lot of adjustments. The requirements for the latest viz's are especially tricky (made even harder that their data source is Excel, so I'm unable to use SQL to do a lot), and there were a few times where I had to take some time to get the data working properly and displaying in the proper way. A few times I even said "I don't know if Tableau can do that" (which shocked the client, because almost always I have the answer ready to go), but in every case it was simply a matter of understanding exactly what processing was required and how Tableau was looking at the data. It was fun to to have a challenge like this and by the time we finished on Friday we had everything working and the client was super-impressed that what they asked for was doable (because there were several things that just weren't possible in Excel without a lot of hard-coding).
Anyway, apart from raving on, this post is trying to say 2 things that everyone should remember - if the numbers are there Tableau CAN do the calculation, just keep trying until you get it, AND don't be afraid to dream up a different way of displaying the data to see if it tells a better story/explains the data better.