Playing Control or Combo in Legacy

One of the recurring comments about Legacy is the non-viability of Combo or Control in this format, supposedly because of the dominance of Threshold or Goblins. Combo is indeed quite absent from the metagame, and Control is limited to weak board control decks which cannot do anything else other than crushing creatures (R/W Rift or Mono-White Control, for example) and are thus usually relegated as pure metagame decks. Oddly enough, the four decks I have been playing after Grand Prix: Lille with a good success are all either Combo or Control decks…