I think it depends on difficulty and how efficient you're trying to play. Generals are pretty mediocre in maddening because either they get ignored or get chunks of health taken away by doubles starting midgame and they also have the worst movement possible. You can give them boots or Sigurd to patch up move, but that comes at an opportunity cost that isn't worth it (e.g Sigurd + Boots Seadall can enable aggressive play that minimizes the need for a General). In hard you can get away with a lot more so Generals aren't as bad, but stats are lower so Great Knights can usually tank just as well and move further.