A possible treatment to solve a possible problem sequence dawned on me. I'm not sure how to formulate rules to handle this, but I'll give an example.
Suppose, for the sake of discussion, that the sequence is something like:
Perhaps Opener made a "fake reverse" for some tactical reason and holds a spade fragment. From Opener's perspective, the trump fit is going to be spades, but from Responder's perspective hearts is agreed.
Suppose further that the partnership agreement is that a 3♠ call by Opener is best treated as a cuebid, with Opener free to correct any heart contract to spades later if appropriate. Thus, Opener could simply bid 4♠ now or later as a "focus correction."
As an example, the auction might be...
4♠, where 4♠ is treated as showing a contextual minimum and a spade fit (2♥ being thereby proven to have been manufactured).
Or, the auction might be...
4♠(focus clarifying, no club control)
Something like that.
These sequences seem to have some merit, from Opener's "I have a problem" perspective. Whereas your approach might not result in problems like this, it seems that sound bidding could feature such auction types with such problems in an intelligent, if minority, approach.
So, assuming that this type of (nonsense?) bidding appeals to you, there is nonetheless a problem -- what if Responder bids 4NT (RKCB) first?
One solution is for Opener to not bid this way unless his answer to RKCB would be 5♣ or 5♦ (and perhaps some also specific-kings limitations as well).
An alternative idea is for the partnership to have certain discussed sequence types where "focus clarifying responses to RKCB" are used.
Thus, assume the auction described above (1♦-1♠-2♥-3♥-3♠...) but where Responder now leaps to 4NT as RKCB. The "focus clarifying" responses (if agreed for a sequence like this -- where Opener makes a reverse into hearts after a spade response) would be:
5♣ = 0/3
5♦ = 1/4
5♥ = 2 without (hearts confirmed)
5♠ = 2 without (spades now agreed)
5NT = 2 with (trumps still in limbo)
Notice how Kickback by Responder would help in this specific situation.
A similar situation might occur after a jump shift to 3♣:
3♣-4♥(RKCB for clubs)
4♠ = 0/3
4NT = 1/4
5♣ = 2 without (clubs agreed)
5♦ = 2 without (diamonds refocused)
5♥ = 2 with (still unclarified position)
When precisely to use this tool (if ever) should obviously be discussed.