docs: variables, review feedback

Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>

Author: oharboe

docs/user/FlowVariables.md

@@ -42,8 +42,7 @@ It is an ongoing effort to move variables upwards in the categories below.
 |--------------------|----------------------------------------------------------------------------|----------------------------------------|-----------------------------------------|-----------------------------|-----------------------------------------------------------------------|
 | **Trivial**         | Automatically determined by tool with near-optimal results.              | None (unless debugging)                | Buffer sizing, default layers           | **High** – can be hidden     | Best if invisible; surfaced only in debug or verbose mode.           |
 | **Easy**            | Requires input, but easy to tune using reports or visuals.               | Moderate – copy/edit from reports      | `PLACE_DENSITY`   | **Medium–High**              | Smooth response curves, intuitive tuning.                            |
-| **Nasty**           | Affects randomness or non-determinism; results vary by run.              | High – requires multiple runs/sweeps   | `CTS_DISTANCE_BUF`       | **Low–Medium**               | Needs scripted sweeps and statistical evaluation.                    |
-| **Pinata Nightmare**| No clear mental model between value and effect, no accurate way to communicate intent; tuning is long turnaround time guesswork.     | Very High – frustrating trial-and-error, few users, if any, can even attempt to succeed | RTLMP_FENCE_LX | **Very Low**                 | Should be deprecated, automated, or hidden from normal usage.        |
+| **Nasty**           | No clear mental model of small changes in values with large effects. | High – requires multiple runs/sweeps   | `CTS_DISTANCE_BUF`, small changes can have large effects on skew and quality of results. Small changes to independent inputs, such as RTL, can invalidate earlier "good values".  | **Low–Medium**               | Needs scripted sweeps and statistical evaluation.                    |
 
 ## Platform