I'm really not a fan of the whole "line-position" formula for describing players/potential, e.g. third line center, second pair defenseman.
I get that it is just the way things are done and always have been done. And I don't expect I'm going to change the paradigm on my own, but I'm hopeful that I can at least plant the seeds in some people's heads.
Hockey is way to complicated a sport for this simplistic line-position structure. For starters, when assessing a prospect's potential, even assuming we are projecting a player for his prime, who knows what that player's situation will be when they're 24 or 27. At 24 they could be playing mostly on a weak team's top line, and then at 27 they've signed as a UFA with a powerhouse and play on the second and third lines.
And that leads me to my next point, within a single season and even a single game, coaches juggle line combinations. You might say "well I just mean they will play mostly on the second line" but meh - for one thing, a quick look at Dobbers line combination tool will show that players tend to play on a lot of different line combinations throughout the season, and often the difference in percentages between their top few most common line combinations isn't that big. For another thing, it is often difficult to distinguish which is a team's first from second, or second from third line.
And then perhaps the most important point: the line-position formula doesn't account for special teams. The Sens center situation this season is the most perfect counter-example I could have imagined. It is impossible to try to predict right now who will fit where, and that is precisely because there won't be a discernible answer. At even strength they will be bounced all over the place depending on performance, opponents and line-matching, and all four will see regular minutes on both special teams, and those likewise will vary based on performance and situations.
I suppose if I'm giving the line-position formula the most charitable understanding, then it would really just mean ranking the centers 1-4 by ice time, but the problem is that's not what most fans think when they hear this.
So what is the alternative? Some may have noticed I used a minute range formula (I've somewhat arbitrarily decided to use a three minute range). So for example, I might say MacKinnon is a 20-23 minute center; he is occasionally over or under but generally in that range.
Looking at the Sens centers this year, I would predict Pageau and Tierney are 15-18 minute centers, White will be 16-19, and Anisimov will be 14-17. I expect their ice time to rank: White, Tierney, Pageau, Anisimov. But that doesn't mean Anisimov is a fourth line center. He'll likely play mostly on a scoring line at even strength.