...if you're already a top team, you don't need a bunch of up years. Most of the guys you're penciling in for -1s are really good players. :) The Mariners just need some of the young guys they do have to do reasonably well and they're right there with the Astros.
We'll remember again that James' fine study -- see the front page of Bill James Online for the article, which is probably behind the paywall -- has its limitations. Every player is a +1 or a -1, regardless. If James Paxton goes 25-3, 1.97 and Felix goes 15-10, 3.75, that's going to be plus one and minus one versus career norms. Also, if Hisashi Iwakuma does a little skosh better in terms of K's, BB's, HR's, etc but only pitches 90 innings, that's a +1.
But still. It means SOMETHING when you say "the Cubs last year were +17 -8. The Indians last year were +13. The Royals in 2015 were +15 -9. The Giants in 2014 were +13 -9, but were only +6 -7 pitching." By the time you add up a whole ROSTER of these seasons for a team, things start to even out. Maybe 'Kuma will only throw 90 innings and have a slightly down year ... but maybe Max Povse will throw 85 good innings.
THE GOOD, THE BAD & THE UGLY Dept.
It hits you right off that the Mariners are already assured of having several pitchers with minus seasons:
1. Felix about a 97% chance of being bad, compared to his career averages
2. Yovanni Gallardo's old-timey career numbers are pretty good. 99% chance of a minus year LOL
3. Edwin Diaz can't possibly match last year
4. Hisashi Iwakuma must pitch VERY well to match his 63-37 career standards
5. We are talking about basically the M's most important 4 pitchers here (well, y'know)
Even James Paxton has high standards to hit here. He's got 8.0 strikeouts, 2.8 walks, and 1.0 homers lifetime. Remember, bulk innings counts are not the point within this little pennant lens.
We all know that Robinson Cano and Nelson Cruz must be pencilled in for "down" years according to the exacting standards of their own career norms. Jean Segura will regress ...
Waitaminnit waitaminnit! It's Nelson Cruz' career OPS+ we're talking about in this system, isn't it! :: slaps head :: Boomstick has a 126 career OPS+; it is the last three years he's been a 150 hitter. Hold on! He's odds-on to have an UP year by this system!
:: whew :: Also Jean Segura has a 93 career OPS+. He is GOING to have a good "Bill James Pennantwinner" year. If the Mariners need 12-15 players having good years by this system, Jean Segura is a MORTAL LOCK for the first one on the list.
YO' TURN NOW
It would be fun to see Denizens' list of the 12-15 Mariners most likely to have good seasons by their own standards. Yes, Mitch Haniger would count as +1 if he beat his 2015 season. No, I don't know exactly how James would figure Dan Vogelbach or other "pure rookies"; figure a mediocre expectation for a rook and guess whether Bach would beat that. Or maybe, just for fun, peg him as likely to exceed Adam Lind's .286 OBP last year?! Yes, it would be reasonable to say "Either Max Povse or Chris Heston will emerge and I'm giving that +1."
James' system counts hitters with 200+ AB's, I think, assuming the hitter deviated from his norms by a good bit in the part-time role. If some guy had +0.4 WAR last year and +0.5 WAR this year, that's a "non-impact" season. There are about 25 counting seasons in every teamwide James Year.
Hmmmmmm. Does it seem likely to you that Dipoto's kids are likely to score 14, 15 players out of 25 who do well? Segura, Mitch Haniger, Guillermo Heredia, Mike Zunino, Vogelbach, Miranda, the nameless Spaghetti reliever ... seems a good number of these UP seasons almost built into the roster. Maybe it ain't so bad as it seemed looking at Felix and Gallardo.
Health counts, correct?
1. You need Seager, Cruz and Cano to stay healthy. Well, 2 of the three, anyway. Let's call it Cano and Seager, healthy and at 125-ish OPS+ (better is better).
2. Age arc says Cruz must fall off, but my eye tells me he looks 31, not nearly 37 (July 1). Let's say that if he hits more than 30 bombs then I'm darn tickled.
3. Segura doesn't have to hit like he did last season to have a good year. If he matches his '13 line of .294-.329-.423 (105 OPS+), then he's had a good year. IF he hits like he did last year then we can absorb some Cruz or Cano decline.
5. Somebody in LF (of course, somebody will play well in LF, as we have plenty of rolls at that dice)
6. Zunino hits .230+
7. Kuma, King, Paxton throw 170 innings each. (the other two guys in the rotation, I'm not too worried about. We have lots of good young guys and Smyly will be pretty good)
8. Diaz to stay healthy and not suddenly lose control.
On any ONE of those things, I'm pretty dang confident. If we get 7 to happen, we're a playoff team.
Zunino was the first who came to my mind.
I'd list Smiley as a + year and if it's the case then only one of Felix/Kuma must have a solid year.
The longest part of the list could be those with no significant MLB time to + from. Vogelbach, Haniger, O'Neill, Heredia, Gamel, Motter, Simmons, Whalen, Moore, Vieira, Povse, Pazos, Overton, Curtis, Altavilla even. To get to 15, some of those names must appear. And if you've got Vogue, Maniger and O'Neil on your + list then a Cruz collapse would seem to be be covered. Mostly.
I'd start that part with the first 4 and Simmons, Altavilla and Vieira. The SP backups I'll pick 1 of (like LF), Seager (yup,up), Segura, Paxton, Martin and Zunino makes 13? Can I take Felix over the last 2 years? And Cruz over career. Dyson in quantity though likely not quality or rates anyway. Oh, forgot to re-list Smiley. There's my 17 then.
Of the 4 Mariners playoff teams, how many have had a significant number of important +1 players? Offhand, it seems that 2001 and 95 did, but did 97? In 2000, I guess Arod and Edgar were +1s, but no one else on offense. Maybe Panigua, Halama, and Sele were among the pitchers.