ground-game/workplans/GROUND-WP-0005-difficulty-tiers-and-pressure-dial.md

---
id: GROUND-WP-0005
type: workplan
title: "Difficulty tiers (threshold ratio) and optional Pressure dial"
domain: consumer
repo: ground-game
status: finished
owner: bernd
topic_slug: whynot
created: "2026-08-04"
updated: "2026-08-08"
origin: residual
origin_ref: GROUND-WP-0004
state_hub_workstream_id: "7a91ccc8-fe04-5831-b427-677b2a49a972"
---

# Optional difficulty control after GR-E01 arithmetic is settled

**Origin residual of GROUND-WP-0004.** Arithmetic winability is closed:
Surface + hidden `1..k` → available 6/9/12; Standard thresholds 5/7/9.
Design history:
[`history/260804-threshold-reachability-and-difficulty.md`](../history/260804-threshold-reachability-and-difficulty.md).

**Finished 2026-08-08.** No named Learning/Mastery **threshold** tiers for
now. Pressure / difficulty variation lives on modular **aspects** (see
[ASPECTS.md](../editions/ASPECTS.md) `difficulty_accessibility` and
`problem_stress` / `problem_deal`).

## Baseline receipt — [GROUND-RPT-0002](../reports/260805-clay-borg-difficulty.md)

clay-borg proposed **no threshold changes**. Spread 72–100 points means
single-policy win rate is not difficulty. 2p tightest; 5–6p play-matters-more.

## Dial candidates (disposition)

| Dial | Disposition |
|------|-------------|
| **L1 Threshold ratios** (Learning / Mastery) | **Not now.** No measured need; RPT-0002 against moving 5/7/9. |
| **L2 Scope / composition** | **Preferred.** `problem_stress.scoped` measured (RPT-0005); further dials via `problem_deal` and profiles under [WP-0008](GROUND-WP-0008-composable-rules-modules.md). |
| **Flat global stress** | **Rejected** as difficulty lever (H1 / RPT-0004). |

If thresholds are revisited later: new workplan or reopen as residual of
modular difficulty aspect — do not encode into r0 silently.

## Task: decide whether to add named tiers

```task
id: GROUND-WP-0005-T01
status: done
priority: low
state_hub_task_id: "59e584f6-afba-5ac3-aab9-8e793047f3ed"
```

**RULED 2026-08-08:** Keep **Standard thresholds only** (5 / 7 / 9). Do
**not** add named Learning/Mastery threshold-ratio tiers at this time.

Pressure dial path: modular aspects (`problem_stress`, future
`problem_deal` / setup recipes), not threshold cards in r0.

## Task: encode tiers in edition data (if T01 says yes)

```task
id: GROUND-WP-0005-T02
status: cancel
priority: low
state_hub_task_id: "5569d823-1010-58a7-a97d-a1574c024aa8"
```

**Cancelled 2026-08-08.** T01 said no named threshold tiers. Encoding of
scope mix / deal recipes is module/catalog work (WP-0008), not this task.