rearrange slightly

guide/src/parallelism.md

@@ -125,15 +125,16 @@ in parallel. It is also possible to spawn threads in Rust that acquire the GIL
 and operate on Python objects. However, care must be taken to avoid writing code
 that deadlocks with the GIL in these cases.
 
-In the example below, we share a `Vec` of User ID objects defined using the
-`pyclass` macro and spawn threads to process the collection of data into a `Vec`
-of booleans based on a predicate using a rayon parallel iterator:
-
 * Note: This example is meant to illustrate how to drop and re-acquire the GIL
         to avoid creating deadlocks. Unless the spawned threads subsequently
         release the GIL or you are using the free-threaded build of CPython, you
         will not see any speedups due to multi-threaded parallelism using `rayon`
-        to parallelize code that acquires the GIL.
+        to parallelize code that acquires and holds the GIL for the entire
+        execution of the spawned thread.
+
+In the example below, we share a `Vec` of User ID objects defined using the
+`pyclass` macro and spawn threads to process the collection of data into a `Vec`
+of booleans based on a predicate using a rayon parallel iterator:
 
 ```rust,no_run
 use pyo3::prelude::*;