A running theme here is that the Royals offense is successful due to BABIP luck. There's of course a strand of truth to that. League BABIP is .297, and the Royals BABIP is .309. They walk less and strike out less than any other team in baseball. There's at least a little bit of smoke and mirrors.
All stats in this article are before last night's games.
However, if you want smoke and mirrors, take a look at the Twins. Their offense is below average, and they don't have the defense to make up for it. Their pitching isn't great either. Yet, the Twins are 50-43.
Outside the BABIP luck part of a smoke and mirrors offense, there is also sequencing luck. For example, last night the Royals scored four runs in the seventh inning. They bunched together a walk, a single, a bunt grounder thing, and a home run. However, the home run came last, so the homer was a three run kind and not a solo kind. That gets at the essence of sequencing luck.
Another part is, for lack of a better term, scoring position luck. This is the phenomenon that RBIs attempts and fails to measure - the ability to bring in guys on base. Two years ago, the Cardinals hit hilariously well with runners in scoring position (37 percent above average), which allowed their overall slightly above average offense (only four percent above average) to score tons of runs (3rd in runs scored).
Last year, the Cardinals offense got a bit worse, but they scored far fewer runs (ranked about 16th in overall offense but 23rd in runs scored). A huge part of that was that the Cardinals offense fell back down to Earth with men in scoring position. Their offensive output with men in scoring position matched their overall offensive output - slightly below average.
The example of Moose's home run last night was to point out an example of the Royals offense performing well with runners in scoring position. However, that does not reflect the overall season. Below is a graph showing the difference between a team's wRC+ with men in scoring position and their wRC+ with the bases empty. The blue bars show the teams who perform better with men in scoring compared to bases empty; the red bars show the opposite. The color intensity matches the sort - the darker the color, the larger the magnitude of the difference.
You'll see the Twins near the top here, which means they have performed a lot better with men in scoring position than with the bases empty. Near the middle, you'll find the Royals with a slight positive difference. Overall, the Royals have performed slightly better with men in scoring position than with the bases empty. This phenomenon is not a significant factor in their offense.
Now, that's not to say that the Royals offense isn't at least a bit lucky. I mentioned their above average BABIP earlier. FanGraphs has their BaseRuns calculation, which attempts to strip out all the luck-based stuff - the smoke and mirrors. The Royals have been a bit lucky, gaining five wins by including the luck-based stuff. That's a big gain, but compared to the rest of the AL Central, it's not. The Royals would still lead the AL Central if a simulation ran the baseball season.
Despite my love of numbers, I'm glad that simulations don't run the season.