[straube]

While I'm mulling over 1C-1D as a universal semipositive, how about using it for at least passed hand?

P P 1C P...

1D-any semipostive
1H-DN
etc-GF at +1

After 1C-1D
....1H-as hearts or GF relay

After 1C-1H
.....1S-as GF relay

leaving opener the ability to bid a suit naturally at the 2-level

GF +1 should not be a problem because responder's hand is limited to like 8-10 and we will thusly save on control steps.

Contrast this to standard Precision in which (for PH) we're probably looking at 70% in the 1D response. We have much more need to differentiate the DN and SPs for passed hand.

[dake50]

Look at third hand club. Don't remember who published that.
His point was as yours: maxpass; middling; and double
negative need to be distinguished.
Not much frequency for GF, so lump those into few responses.

[rbforster]

Split range 1♦ reply probably works well too, most GF or DN, leaving most responses for descriptive SPs and higher ones for specific GFs.