Merge branch 'docs/follow-up-parallel-run' into 'master'

Refactor new content for stage keyword

See merge request gitlab-org/gitlab-ce!25953

doc/ci/yaml/README.md

@@ -268,15 +268,9 @@ There are also two edge cases worth mentioning:
 
 ### `stage`
 
-NOTE: **Note:**
-By default, when using your own Runners, the GitLab Runner installation is set up to run only one job at a time (see  the `concurrent` flag in [Runner global settings](https://docs.gitlab.com/runner/configuration/advanced-configuration.html#the-global-section) for more information).
-Jobs will run in parallel only if:
- - Run on different Runners
- - The Runner's `concurrent` config has been changed.
-
 `stage` is defined per-job and relies on [`stages`](#stages) which is defined
 globally. It allows to group jobs into different stages, and jobs of the same
-`stage` are executed in `parallel`. For example:
+`stage` are executed in parallel (subject to [certain conditions](#using-your-own-runners)). For example:
 
 ```yaml
 stages:
@@ -301,6 +295,17 @@ job 4:
   script: make deploy
 ```
 
+#### Using your own Runners
+
+When using your own Runners, GitLab Runner runs only one job at a time by default (see the
+`concurrent` flag in [Runner global settings](https://docs.gitlab.com/runner/configuration/advanced-configuration.html#the-global-section)
+for more information).
+
+Jobs will run on your own Runners in parallel only if:
+
+- Run on different Runners.
+- The Runner's `concurrent` setting has been changed.
+
 ### `only`/`except` (basic)
 
 `only` and `except` are two parameters that set a job policy to limit when