---
title: "When a Small Experiment Starts Touching Too Much"
canonical: https://dxdev.com/blog/2026-04-13_smaller-blast-radius/
datePublished: 2026-04-13
---
A useful experiment can become hard to trust when it quietly reaches shared work that was never part of the original question.

A team starts a small experiment to answer one question, then discovers it touches shared rules and work that were never part of the original test.

## Find the smallest change that can answer the question

Learning scope and change scope should not silently expand together. The practical boundary is the smallest experiment that can answer the question without touching unrelated shared work.

Name the question first. Then ask which dependency, shared path, or existing behavior would be touched only because the experiment grew beyond what it needed to test.

## Where AI fits

AI can map the stated goal, nearby dependencies, and the smallest learning boundary that would let the team investigate safely.\n
## The human decision

People define scope, authorize changes, and retain rollback authority. Anything outside the learning boundary needs separate justification.

## The lesson

A small experiment becomes hard to trust when it quietly reaches shared work that was never part of the question.

The Build Log companion explains how a prototype became reviewable only after it was separated from shared purchase logic.