Narga's post from SF's RD tier list.
Okay, I don't know what to do with Rolf(T).
He starts with 19str and 21spd. By level 10, he has 25.75 str and 25 spd. At level 1 to begin, he gets to fight level 7s to 9s mostly in the first few chapters. On a hit, he gets 8 to 9 exp. On a kill, he gets 29 to 32 exp. It shouldn't take him too long to reach. Also, he has a 56% chance of at least 24 AS by level 7. 6 levels could easily happen by chapter 3-4, at which point 24 AS is good enough for most of our doubling needs (except 2 warriors, 5 swordmasters, 1 boss). 25 AS may not happen for 3-5, since level 9 only sees a 52% chance of having 25 AS, and level 10 gives him 64% (and 25.05 on average). But 24 AS is mostly good enough again in 3-7, since there is just 1 warrior with 21 AS and 5 swordmasters and any DB units with >20 AS to start. Also, 2 swordmaster reinforcements and 3 warrior reinforcements, but by turn 7 he should easily have level 10, considering that is 9 levels in 6 and a half chapters while being rather underleveled. So now he has 41 or 42 mt with the silencer (40 or 41 with steel forge) and doubles everything Shinon does and depending on who Shinon supports, Shinon(N) may actually be missing one or two ORKOs that Rolf can pull.
(note: in response to possible inquiries about what happens the 44% of the time he doesn't hit 24 AS by 3-4, I'd like to let you know that in 5 levels he has a 41% chance of at least 24 AS, so he could easily double some in 3-3. Doubling in 3-3 and 3-4 some of the time, not doubling in either some other times, and only in 3-4 other times, 41% isn't far from 44% so it evens out over time. He even has a 24% chance of at least 24 AS in just 4 levels. And a 32% chance of at most 23 AS in 7 levels, but going to far off the median for just Rolf is a little extreme.)
From this point on, since we don't generally want either one of these attacked on enemy phase and Rolf's 39hp/16def is enough to keep him alive if we need to put him in danger once or twice, Rolf isn't really any worse than Shinon until Shinon promotes. Rolf caps str and spd by level 12 (60% for spd to cap by level 12, 71% for str to cap by level 12). He has a 51% chance of having 41 hp or less and 49% chance of having 42 hp or more. Bexp basically goes into hp and skl, then def or lck. HP will cap pretty quickly at this point, as just one shot of bexp by level 16 means hp is capped. At this point, Rolf could either early crown or continue to try for some bexp levels to get skl/def/lck. Point is, he could probably hit 22 def before promotion, possibly more. Shinon should have 29 def or so by 4-E-1 for the double bow, but Rolf could hit 26 def by then, reasonably. Also they'll have about the same hp. So Shinon is definitely more durable, but only by enough to push his mt to be #HKOd values up by 3. Also, Rolf can be at lower levels than Shinon to ORKO Generals. 51hp/31def needs 57mt to ORKO. Rolf has this at 20/5. Even if Shinon had enough bexp to go from 23.8 to 26 in tier 2, that's only 28 str and he needs 20/11 just to hit 32 str (20/10 would be 31.6, so it could happen then, too). And there are also 52hp/32def Generals that require 33 str, something Rolf hits pretty easily and Shinon needs 20/13 (20/12 is only 32.4).
So, Shinon >> Rolf(T) is obviously true, and I'm not disputing that (That is, I'm not even suggesting it is only one '>' rather than two). But aside from 3-5, Rolf is matching Shinon's output by 3-4. Shinon's earlier promotion mostly amounts to 3 range and him not losing str to Rolf, and thus the things Rolf can ORKO because of capping tier 2 str, Shinon can ORKO because of the promo bonuses. So 3 range a little earlier is what it comes down to. Also, a little more durable with the double bow. However, they should both be looking at a 3HKO from reds and a 2HKO from whites. Also, Rolf could very well support light/water/thunder if his def isn't enough to reach 3HKO. Shinon supporting that isn't going to push him to 4HKOd. And a cover tile makes each of them get past 3HKOd from reds and 2HKOd from whites. So even in 4-E Shinon isn't that much better.
Of course, in early part 4 Rolf may have some issues, and he may not hit 34 AS by Deg, but by spirits it could happen. Rolf has 28 AS after promotion, and I'm not sure when that happens. He needs ~level 20/5 to double the halbs in 4-4, for example. 20/7 for just a 56% chance (assuming capping in tier 2) of doubling warriors in that chapter (except 2 that have 28 AS). So again, Shinon > Rolf.
But I'm thinking that Rolf is doing well enough for long enough that he could be upper mid. Low end of upper mid, but he's ORKOing a significant portion of every map for a very long time when many other units above him are not. Also, he starts with the same speed Titania(N) has in 3-P and 3-1, and he does have 29 mt with the steel bow and 27 mt with the killer bow (if Shinon takes the steel bow from Rolf). It isn't horribad. And while he's not building much utility during the time before 3-4 (unless he attacks things he can double), he's definitely a worthy member of the clean up crew, so getting exp for him is easy. It also isn't slowing us down, considering those weakened enemies have to die somehow anyway. Also, fyi, in 3-2 if he is level 4 he has 21.25 str and 22.35 spd. With a forged steel that is 36 mt. He can actually ORKO a fair number of paladins. And obviously sages (even without a forge). Aside from 2 generals he 3HKOs, he 4HKOs the others. But that is still a 2RKO anyway. Also he 3HKOs dragonmasters. Doubles all of them, too. So even in 3-2 he's actually far from horribad. Sure, Shinon is better against a couple of paladins if he has 22 str, and he is better against the two halbs. But as soon as Rolf hits level 4 (should be partway through the chapter, if not at the beginning) he's already comparing. (Oh, without forges Shinon only has 32 mt anyway, assuming he pulled 22 str. So neither of them are all that good here and Shinon could have = mt with Rolf as well. They just 2HKO (2RKO) swordmasters and ORKO sages and bishops like they do with forges. Otherwise, on the rest neither ORKO anything anymore and they are quite miserable against Generals and Dragonmasters.)
Shinon is, of course, a fair amount better in 3-3 with a larger number of 20 AS enemies.
Now, obviously having little enemy phase ability hurts him, just like Shinon. But Shinon is in high tier because of his ability to ORKO when others can't. Rolf can do the same job about 80% of the time Shinon can do it. If Shinon is high tier for that, then Rolf should be able to be upper mid for doing the same job just as well throughout a lot of the game (or almost as well) and not hurting us at all when he isn't.
Oh, and Rolf(T) probably starts with almost S bows, if it matters (A rank in PoR gives 120 wexp, so 60 out of 60 for B -> A and 60 out of 70 for A -> S). I think he'd do enough attacks with steel by 3-4 to wield the Silencer anyway, considering he just needs 20 attacks in at most 42 turns. Of course, probably < 42 turns, but surely at least 25 turns. Plus Rolf's bow has 8 mt and gives 4 wexp, so on things like sages that he will 2HKO regardless or things that have been weakened he can probably use that. 3 attacks with Rolf's bow mean one less total attack needed.
16(3) + 3(4) = 60 (19 total attacks).
12(3) + 6(4) = 60 (18 total attacks).
8(3) + 9(4) = 60 (17 total attacks).
Considering when he doubles that's 2 attacks, he could pull an A in less than 18 encounters rather easily (18 encounters in 25 turns is him attacking something on 72% of his turns). Even with a fair amount of time spent doing clean-up. 5 doubles + 10 not-doubles = 60 wexp without even using Rolf's Bow.