proas

#1 Opening only 2♣ - unbalanced hand and 21HCP. Bidding system "2♣ strong" isn't easy in this case. Here are some bidding examples (Opp's bid Pass): 1) P - 2♣ 2♥[8+, 5♥+] - 2♠[5♠+] 3♦ - 3♥ 4♦!(1) - 5♦!(2) 5♥ - P/6♥(3) (1) Cue. Don't cue bid in the ♠! If I had a single A♠, then I would cue bid 3♠; (2) Void ♦; (3) analysis and choose 2) P - 2♣ 2♦ - 2♠ 3♥[5♥+] - 5♦!(1) 5♥!(2) - P/6♥(3) (1) Exclusion Blackwood; (2) 0 Aces; (3) analysis and choose 3) P - 2♣ 2♥ - 3♥ 3♠!(1) - 4♣!(1) 4♦!(1) - 5♦!(2) 5♥ - P/6♥(3) (1) Cue; (2) Void ♦; (3) analysis and choose 4) P - 2♣ 2♥ - 3♥ 3♠!(1) - 5♦!(2) 5♥!(3) - P/6♥(4) (1) Cue; (2) Exclusion Blackwood; (3) 0 Aces; (4) analysis and choose Note! I don't recommend bidding the 4NT-Blackwood by the opener, because if the respondent shows one ace, it isn't known in what suit (A♦? A♠?). It depends on whether to play 5♥ or 7♥.

2♦(weak, 6+♦) - 2♥/♠ - X Dbl is penatly, because the opener defined his hand.

#1 Opening with hand W can only be 2♣. Because after opening 1♠ can missing a game in 4♠/♥ or a slam, if the responder bids Pass. Even with the shape at E: ♠4 ♥87652 ♦65432 ♣J4 slam in ♥ is real!