Schedule strength isn't always a reliable indicator as teams improve or worsen from one season to the next.

We should keep that in mind while discussing how the 2013 schedule could shape expectations for teams nearly five months before the regular season.

I do think it's interesting to note that the 2013 schedule could work against the Seattle Seahawks on two fronts while favoring the San Francisco 49ers on at least one.

Could these differences help decide the NFC West race in 2013? Lets walk through them.

Kickoff times

Having five kickoffs at 10 a.m. PT works against the Seahawks simply because it's tougher playing so early in the day immediately after traveling West to East. We've discussed this subject several times over the years, usually pointing to won-lost records for road games based on start times. I'm not sure that's a great way to measure the impact of travel. Anyone who has traveled West to East knows it's tougher, and that should be enough whether or not on-field results appear to line up.

2001-12 Road Records by Kickoff Times

In the Seahawks' case, they've been outscored by 4.6 points per game in the first halves of 10 a.m. PT kickoffs since 2001, according to ESPN Stats & Information. The deficit was 2.1 points per game in first halves of road games kicking off between 1 p.m. PT and 1:25 p.m. PT.

I've singled out first halves on the theory that a team traveling West to East for an early game could need a half or so to get going. Some thought the Seahawks appeared to play that way when falling behind by 20 points to the Atlanta Falcons in an early kickoff during the playoffs last season. They were much better after halftime.

The deficits after halftime for Seattle in these games were much smaller (1.6 points per game in the early kickoffs, and a half-point per game in the later ones).

The chart at right breaks down the won-lost record by kickoff time for the five teams either on Pacific time or, in Arizona's case, aligned with Pacific time part of the year.

Again, I'm not certain that type of evidence is compelling. There aren't very many games. Many other factors could come into play for specific games. However, I do know traveling West to East can be tough on the mind and body. Seattle has five of these 10 a.m. PT games. The 49ers have one of them. Advantage, 49ers.

Schedule strength by venue

Seattle went 8-0 at home last season and 3-5 on the road. The Seahawks' home opponents for 2013 had a combined .438 winning percentage last season. That sounds great for Seattle, but it's not like the team can improve upon 8-0. There's nowhere to go but down regardless of which teams visit CenturyLink Field.

2013 Schedule Strength by Venue

The flip side for Seattle is a much tougher-looking road schedule (.594). The difference between those home-road records -- plus-156 percentage points from .438 to .594 -- is tied with Denver for largest in the league.

The 49ers, meanwhile, generally have their tougher opponents at home, where San Francisco might be expected to win regardless. Their home-road disparity -- minus-172 percentage points from .605 to .434 -- is the largest in the NFL.

Nik Bonaddio and Keith Goldner of numberFire recently pointed to the 49ers' home schedule as one reason San Francisco enjoys one of the NFL's five easiest paths to the playoffs .

One more time: There's a fair amount of subjectivity and uncertainty here. As a general rule, however, I think the 2013 schedule favors the 49ers while lengthening the odds for the Seahawks.

The St. Louis Rams also face a tougher schedule on the road than at home. The gap between winning percentages for home and road opponents -- .465 at home to .613 on the road, or .148 -- is tied for second-largest in the NFL behind those for Seattle and Denver. The Arizona Cardinals' home-road disparity lines up closely with that of the 49ers.