Addition. By Subtraction.

I’m not going to argue the point that some of my pre-season optimism in the Royals is not entirely grounded in reality. It’s March. Hope Spring Eternal, and all that jazz. My playoff hopes notwithstanding, on paper this team looks like about a 78-81 win team to me, which is actually quite an improvement from last season.

(The Royals won 75 games last year, but based on their run differential – they were outscored by 90 runs for the season – they should have finished around 72-90. Give the Mexicutioner credit for those extra three wins. The Royals lost just one game all season that they led after eight innings – you might remember it – after losing at least three such games in every season since 1995. More to the point, they were 20-18 in one-run games, continuing the turnaround in that category since Joakim Soria was acquired. They were 21-22 in one-run games in 2007, which doesn’t sound great, but remember: from 1996 to 2006, the Royals were the worst one-run team over an 11-year span in the history of major league baseball.)

I see the Royals improving because I think that we’ll see an across-the-board improvement from the trio of Zack Greinke, Alex Gordon, and Billy Butler, more than enough to make up for the inevitable regression from Mike Aviles, and that the rest of the roster should perform at roughly last year’s level.

So you figure two-game improvements from each of the young’uns (we need a nickname for those three), and you can tack on six more wins to last season. That’s 78 wins if you think that the Royals were really a 72-win team last year, or 81 wins if you think the bullpen will help them play a little above their talent level again.

But here’s the thing: the greatest improvement the Royals can make this season won’t come from their good players playing better, it will come from their bad players playing less. Last season, the Royals gave 892 at-bats to the trio of Ross Gload, Tony Pena, and Joey Gathright. In return they got a .241 average with four homers, three triples, 25 doubles, and 49 walks. The Royals gave over 15% of their playing time to three guys who combined for a .289 slugging average and a .284 OBP.

If they can find a way to avoid writing off nearly two full lineup slots the way they did last year, the Royals are going to benefit from a mighty case of addition-by-subtraction. It’s not a coincidence that in September, when those three guys combined for just 62 plate appearances, the Royals went 18-8.

Here’s how big an impact a Pena-free season can make:

Last season, Mike Aviles hit .325/.354/.480 in 102 games. Of the 27 men who played at least 80 games at shortstop last season, Aviles ranked first in batting average and third in OPS, behind only Hanley Ramirez and (by one point) Stephen Drew. As terrific a season as it was by major league standards, by the standards of Royals history it was unprecedented. Of the 39 times a Royal has played 80 games or more at shortstop for the Royals, Aviles’ .834 OPS ranks #1 overall. The only player within 40 points of his total is Jay Bell, who hit .291/.368/.461 in his one season in KC.

In 2008, Aviles had one of the finest seasons by a Royals shortstop in the team’s history. But in 2009, PECOTA projects a rather massive decline in Aviles’ performance, projecting that he hits just .268/.309/.409 this year, a decline in OPS of 115 points. Aviles’ 90^th percentile projection is still lower than last year’s numbers at .301/.344/.478, which means that Aviles has less than a 10% chance of matching last year’s performance. This isn’t all that surprising, really; Aviles’ performance was as unexpected as it was terrific, and furthermore it was largely batting-average driven. Aviles is a better player than any of us thought, but there’s no question that last season he was propelled by a tailwind of good fortune.

It’s not all that surprising, and it may not be all that relevant either. Why? Because if the Royals get a line of .268/.309/.409 from their shortstops in 2009, it will still be an improvement over last year. That’s how bad Tony Pena was last season. The Royals had the benefit of the best-hitting shortstop in their history 58% of the time – but the other 42% was so bad that for the season, Royals shortstops hit just .249/.281/.351.

That’s how bad Tony Pena was – he was last on both those lists by an embarrassing margin – and that’s how much better the Royals can be if they can find a way to keep him off the roster.

First base wasn’t nearly that bad, but thanks to Gload the Royals had a combined line of .277/.324/.396 with just 14 homers – and seven of those came from Ryan Shealy in September alone. Mike Jacobs is overrated, but he’s just as clearly an upgrade – particularly if the Royals bench him against the tough left-handers.

As important as it is for the Royals to get some true breakthrough seasons from the likes of Gordon and Butler, and a rebound season from Jose Guillen, it’s just as important that they find a way to keep the roster free of guys who have no offensive ability whatsoever. Gload is still around, but even if he makes the roster he’s unlikely to get a lot of playing time. Pena is a longshot to make the roster, and Gathright’s a Cub. From where I’m sitting, while the Royals don’t have a lot of above-average hitters on their roster, everyone on their projected roster (yes, even Willie Bloomquist) has some offensive talent.

The Royals have exactly one winning April in the last 19 seasons, in large part because they go into every season with at least a few regular players who have no business being regulars, and it takes a few weeks of getting their butts kicked before the Royals wake up. Last year Ross Gload was at first base and Tony Pena was at shortstop on Opening Day. This year, the Royals may actually have nine major league hitters in their lineup to start the season. (I said they may – the Spork may put an end to that dream.) If the Royals are serious about contending this year, they can’t afford to spend April learning what the rest of us already know: it’s hard to win with only seven hitters in your lineup.