[clinic · EX-17] Measure position sensitivity for real

[akash-coded]

Exercise clinic. One long-running thread per exercise. Ask here rather than opening a
new thread — the answers accumulate where the next person will look for them.

Exercise: EX-17 — Measure position sensitivity for real · difficulty 🔴

What this exercise asks

Read the exercise first; this thread is for when you are stuck, not instead of it.

Three ways people get stuck on this one

1. Measuring against the extractive generator and reporting it as a model result. It measures the packer, not attention.

2. Not running an ungrounded control, so packer artefacts are attributed to position.

3. One k only. The effect is expected to grow with context length; a single short context says little.

How to ask here

Post the numbers you got, the config that produced them, and what you already tried.
A question with a measurement in it gets answered in one round trip; a question without one
takes three.

If you have finished it, post the write-up in Show and Tell with the
[solution · EX-17] prefix rather than here — this thread stays for people who are stuck.