Bloodwinter Clan and the small unit doctrine on Merlin
BWC ran small unit RvR on Merlin for almost a decade. The doctrine they wrote down, in groups and in keep sieges, is the doctrine the modern siege MMOs are still trying to recover.
The interesting question about Bloodwinter Clan is not whether they were good. They were. The interesting question is why the doctrine they ran on Merlin between roughly 2002 and 2010 has never been fully replicated in the modern siege MMOs that explicitly try to descend from DAoC.
Two answers compete. The first is that the doctrine was specific to DAoC's three-realm balance and would not transfer to two-faction or open-PvP systems. The second is that the doctrine was specific to a leadership culture that the modern audience has not been willing to absorb. Both answers are partially correct. The interesting work is figuring out the proportions.
What the doctrine actually was
BWC ran small group RvR. The standard RvR group in DAoC was eight players, and the BWC operating unit was usually a single eight-stack with a rotating second stack available for keep sieges. The composition was strictly controlled. Every group had a guaranteed crowd-control role, a guaranteed primary healer, an interrupt specialist, and three to four damage roles whose job was to convert the CC and interrupt windows into kills.
This is a very normal-sounding composition. The BWC version of it differed in two ways.
First, the role discipline was non-negotiable. Members did not bring whatever class they felt like playing. They brought the class the group needed, on the night the group needed it, at the level and gear standard the group required. Members who could not commit to that standard did not get to play in the active group, regardless of how socially senior they were. This sounds obvious. In practice, almost no DAoC guild outside of the elite tier enforced it. BWC enforced it.
Second, the operating tempo was twice what most contemporaneous guilds ran. BWC ran active RvR most nights of the week, including nights when the broader server population was thin. The reasoning: the small population nights produced the cleanest engagements, with the fewest accidental third parties, and were the best learning environments for the standing roster. Most guilds treated thin-population nights as off-nights. BWC treated them as the most important practice nights.
These two principles compound. Strict role discipline means that practice nights are useful. Useful practice nights mean that the standing roster's level of coordination keeps rising. A continuously rising coordination ceiling means that the guild's effective combat power, per player, keeps growing relative to the average DAoC group. By 2005 the gap was significant. By 2007 it was structural.
Where this fails to transfer
The modern audience would like this doctrine to transfer cleanly into Throne and Liberty or New World or any of the active siege MMOs. It does not.
The first reason is structural. DAoC's three-realm balance kept the political map roughly equilibrated, which meant that BWC could operate in a contested but not overwhelming environment. The modern siege MMOs all run two-faction or open-PvP systems where any organization that achieves a coordination advantage gets pile-driven by alliance coalitions until the advantage is neutralized. The three-realm structural absorption of BWC's competence is what allowed the doctrine to keep producing returns over years rather than weeks.
The second reason is cultural. The audience that signed up for BWC's role discipline was an audience that had been raised on the notion that an MMO is a hobby that requires consistent attendance and consistent role specialization. The modern audience that plays Throne and Liberty was raised on the notion that an MMO is a hobby that should accommodate inconsistent attendance and flexible role swapping. The two cultures are not compatible. Any organization that tries to enforce the BWC standard on a modern audience hemorrhages members within a quarter.
Where this should still transfer
The principle behind the doctrine is universal. Continuous practice with a stable roster against a credible opposition is the path to coordination advantage. Every modern siege MMO that wants to ship organizations capable of winning at scale has to figure out how to recreate the practice-environment-with-stakes that BWC operated in.
The honest answer is that you cannot fully recreate it. You can approximate it. The current best approximations live in Albion Online's GvG bracket, which structurally recreates the small-group set-piece environment that DAoC's keep sieges used to provide. Beyond Albion, no modern title has built a structural home for sustained small-group practice with stakes, and that gap is the single most important design hole in the current siege MMO wave.
What BWC got wrong
The criticism that lands. The BWC leadership culture was unusually tolerant of internal hierarchy ossification. The same role discipline that produced the doctrine produced a guild structure where the senior officer corps changed slowly, and the back-bench leadership pipeline was thinner than it should have been. When attrition hit the senior officers in the 2008 to 2010 window, the replacement layer was not as capable, and the operating tempo dropped.
This is the standard MMO guild end-state and BWC was not exempt from it. The guild that runs a strict standard is also the guild that has trouble promoting from below, because the strict standard makes it hard to identify which members are actually ready for senior responsibility versus which members are just senior in tenure. BWC erred toward tenure. The cost was visible in the late period.
Verdict
Bloodwinter Clan is in the Legends list because the doctrine was correct, the execution was sustained, and the gap their absence leaves in modern siege MMO history is real. The audience that wants modern games to produce organizations like BWC is asking for something the modern audience itself is not configured to support, and that contradiction is one of the more interesting open questions in the genre right now.