Struggling for two whole days to do some not-terribly-advanced repeated-measures analysis of variance in R. Probably my worst experience with R so far and really an example of where R could do with some centralisation of effort. I have explored six or seven ways to do more or less the same thing, but each approach was too lacking either in documentation or in the statistics department.
I don’t blame the R devs, I blame the tens of thousands of institutions like Universities which are prepared to spend a large fortune on licenses for SPSS and the like. They could switch just some seats to open source solutions like R and spend a bit of the money they saved on bounties to the R community. Then even these holes could be pretty easily plugged.