[DavidKok]

Let's keep it moving. I'm doing away with the spoilers from here on. In no particular order:

• mike777 had the 1♦-1♠; 2♥-3♠; ? start, which I think should set trumps (with lesser spades, instead bid 1♦-1♠; 2♥-2♠; <something>-3♠).
  
• mikeh started 1♣-1♥*; 1NT-2♥*; 2♠-3♥*; ? - here responder is showing a similar hand type, a slam try with long spades, but notably opener has chosen to describe the hand differently (balanced instead of two-suited). We're also one step lower and a spades contract will be played by the other side. I presume 3♥ sets trumps and initiates control bidding - please describe how opener continues. Do you have some (Non)Serious gadget, and how do you weigh the HCP maximum versus the singleton queen in support and unwelcome shape in evaluating this hand in context?
  
• mw64ahw broke out a specialised gadget, bidding 2♣-2♦; 3♥-4♠; 5♠-? where 3♥ showed exactly 1=4=4=4 - quite high for a 19-count when partner had no room to contribute. 4♠ was a slam try setting spades, and 5♠ showed odd keycards and the queen. Unfortunately I think this is too high for partner to make an informed decision.
  
• Cyberyeti bid 1♦-1♠; 1NT-2♣; 3♣-?, also choosing to treat the hand as 17-19 balanced and representing exactly 2=3=4=4 it seems? Over this partner will make a slam try in spades, perhaps with 3♠ if that bid carries that meaning. What are your continuations?
  
• jillybean chose to upgrade into 2NT, also representing the hand as balanced. Over this I play that 4♦ shows a slam try in spades (and sets the trump suit), which partner will use. I imagine you'd respond 4♠ (negative) rather than 4♥ (positive), over which partner is in a difficult spot.

I won't reveal partner's hand just yet, but I can say that partner isn't really interested in keycards. Controls and playing strength are more valuable on this deal, and having tools to establish a slam try in spades by the 3♠ level or so is a major benefit on this deal. Please let me know how your auctions would continue, I'll jump in and provide partner's actions if needed (and you tell me what the options are).

4x1's are problem hands for almost all bidding systems - this is the only hand type that is neither balanced nor has (at least) a five card suit. If you add some strength to the hand it also becomes unattractive to sit back and let partner take the reins. I think most or all of these auctions are still on track for finding good contracts, and it's interesting to see the impact of multiple close decisions.

[mw64ahw]

The other option I have is opening my esoteric unbalanced ♦

Now if the hand is game invitational
After opener shows shape responder indicates strength followed by opener showing shortage

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or
The 2♥ bid shows one of s4(53), s444,xx55 or x45x GI only for the latter after 2♠
Game invitational

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Game forcing

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Game forcing with self-sustaining Spades

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[DavidKok]

Responder has a game forcing hand with spades, but needs shape information from opener before committing to any trump suit and strength information before committing to a slam try. I'm not sure what your game forcing options are over 1♦, but responder can not commit to showing self-sufficient spades in my opinion until opener has shared the hand type and primary suits. I'd like to know what your exact criteria are for showing a game forcing hand with a self-sufficient suit, so that I don't misinterpret your methods.
Do keep in mind though that at the table you can't normally choose a different opening bid after your gadget misfired at the 5-level.