Yes, the Cardinals are too reliant on home runs.
In 2015, the St. Louis Cardinals hit 137 home runs. Going into play Sunday, they have 208 with 14 games remaining, already a 52-percent increase from 2015. The Cardinals have the most home runs in the NL, tied for 2nd in MLB with Toronto. They have nine players with at least ten home runs and four of those players have at least twenty. This power development is good. It’s great, actually, because they have played eleven fewer one-run games this season than in 2015.
The Cardinals have scored 709 runs, and 321 result from a homer. That's forty-five percent of their runs scored! According to Baseball-Reference, 56 of the home runs have been to take the lead in a game. The Cardinals have hit 31 home runs to tie the game. It feels like they have an inability to string hits together because only 78 of their 208 homers have come with runners on base. This is masked by their ability to hit balls out of the park, because what does it matter if you string three hits together to score one run or do it with one swing of the bat?
Most of the time, though, one run is all they get. The Cardinals have hit 130 solo shots in 208 opportunities. Taking a step backward, I thought it would be good to look at how many times the Cardinals have scored two or more runs on a hit that was not a home run. I used the Baseball-Reference game log and sorted by month.
After May, the 2+ RBI hit count took a nosedive and it stayed there for the middle part of the season. This is indicative of a stifled offense. It's one run each time; they can't bundle runs together. The lull in 2+ RBI hits suggest the Cardinals are too reliant on home runs. Again using Baseball-Reference, the Cardinals have 112 hits to take the lead and 51 of those have been home runs. The cherry on top of the sundae: they have homered in 64 of their 77 wins. To get back in a game from behind, the Cardinals have to homer. To take the lead, they might need to homer. To win, they need to homer. Yes, they are totally reliant on the long ball.
As the home run totals have increased, their month-to-month go-ahead homer totals are pretty stagnant. They had six in April, eleven in May, ten in June, and it remained about the same in July (twelve go-ahead homers), August (nine go-ahead homers) and right now in September (eight go-ahead home runs). The increased number of home runs does suggest they rely on the long ball more than they did earlier this season, but not for game-winning or game-tying RBIs.
This emphasis on home runs is a problem because of the Cardinals' seeming inability to score with base hits. They are 3rd-best in the NL average-wise, batting .269 with runners in scoring position. Take that average with a grain of salt. They have limited opportunities, 1149 at-bats, which is 10th in the league and 20th in MLB. The Cardinals are not quite as bad as they seem with runners on, but their opportunities are limited in comparison to many contending teams, since they simply don't get on base as often as they should. Their OBP ranks 13th in MLB, which means that even though they're hitting lots of home runs, almost all of them are solo shots. That's a problem, and it indicates they can't do much of anything without a home run.
Are they a crutch for the Cardinals? Yes. The home run to win correlation is food for thought, but the ability to continuously hit home runs to take the lead (from May – September) suggests the Cardinals can get long-ball hits when they are needed. Hitting a homer in 83 percent of their wins suggests this is part of the game plan they can continue to execute through September and, fate permitting, October. Additionally, the Cardinals have seen an uptick in their 2+ RBI base hits in September, perhaps an indication they are getting slightly, ever-so-slightly less one-dimensional. If you have to pick a single offensive dimension, however, the home run isn't a bad choice.