[JLilly]

Does anyone know of any systems where all (or nearly all) hands above a certain strength are opened 1♣, as well as some stronger-than-minimum hands with primary clubs, but no other hands? That is, no balanced hands or 4441s. Polish Club and An Unassuming Club have these other hand types.

Or a strong diamond system that also has some less-strong primary diamond hands.

The idea is to get very frequent intermediate, Fantunes-style 2♣/♦ openers that pressure opps by taking stronger-than-minimum opening hands out those bids, at the expense of some loss of definition in the strong 1m opener. For example,

1♣ = 16+ unbal all, 17+ bal all, 14-16 6+ clubs, 14-16 5+ clubs and 4 of a major
1♦ = out-of-range-1NT balanced hands, 13-15 6+ diamonds, otherwise unspecified primary-diamond hands, {1,2,3}={3,2,1}=4=5
1M = 11-15(16)
1N = 14-16 or 11-13
2♣ = 8/9-13 6+ clubs, 8/9-13 5+ clubs and 4 of a major
2♦ = 7/8-12 6+ diamonds

4=4=1=4 tells the least-bad lie.

This would go well with 1red transfer responses, with opener jumping to 2M with the 14-16 5♣+4M hand and a fit, non-forcing, while accepting at the 1-level with a bigger hand.

[JLilly]

Or make it a strong-or-long diamond system, with 0+ 1♣ unless 4M+5♦ goes canape:

1♣ = out-of-range-1NT balanced hands, 13-15 6+ clubs, otherwise unspecified primary-club hands, 11-15 {1,2,3}={3,2,1}=5=4, 11-15 4M+5♦ (if not canape)
1♦ = 16+ unbal all, 17+ bal all, 14-16 6+ diamonds
1M = 11-15(16)
1N = 14-16 or 11-13
2♣ = 8/9-13 6+ clubs, 8/9-13 5+ clubs and 4 of a major
2♦ = 8-13 6+ diamonds

4=4=4=1 per usual tells the least-bad lie.

[Gilithin]

Take standard (or RM) Precision and reduce the maximum on your 2♣ opening by a point or two while decreasing the minimum for your club hands in 1♣. The resulting system matches your brief. You could probably do this for several families of system, getting a slightly less efficient method that you will presumably prefer.

[foobar]

JLilly, on 2021-July-27, 02:31, said:

Or make it a strong-or-long diamond system, with 0+ 1♣ unless 4M+5♦ goes canape:

1♣ = out-of-range-1NT balanced hands, 13-15 6+ clubs, otherwise unspecified primary-club hands, 11-15 {1,2,3}={3,2,1}=5=4, 11-15 4M+5♦ (if not canape)
1♦ = 16+ unbal all, 17+ bal all, 14-16 6+ diamonds
1M = 11-15(16)
1N = 14-16 or 11-13
2♣ = 8/9-13 6+ clubs, 8/9-13 5+ clubs and 4 of a major
2♦ = 8-13 6+ diamonds

4=4=4=1 per usual tells the least-bad lie.

I think you are on the right track, and here's my suggestion.

1♣: 16+ any
1♦: Balanced hands outside range
1M: Unbalanced; can be 4441
1N: 14-16 or other NT range
2♣: 6+ ♣, OR 5♣, 4+♦
2♦: 6+ ♦, OR 5♦, 4♣
2M: Canapé with M
2N: 5-5 Minors, limited?