diff --git a/man7/cgroups.7 b/man7/cgroups.7
index 598081a40..a623ce3ef 100644
--- a/man7/cgroups.7
+++ b/man7/cgroups.7
@@ -146,9 +146,14 @@ In this view, a process can consist of multiple tasks
 and called such in the remainder of this man page).
 In cgroups v1, it is possible to independently manipulate
 the cgroup memberships of the threads in a process.
-Because splitting threads across different cgroups
-caused problems in some cases,
-.\" FIXME Add some text describing why this was a problem.
+.PP
+The cgroups v1 ability to split threads across different cgroups
+caused problems in some cases.
+For example, it made no sense for the
+.I memory
+controller,
+since all of the threads of a process share a single address space.
+Because of these problems,
 the ability to independently manipulate the cgroup memberships
 of the threads in a process was removed in the initial cgroups v2
 implementation, and subsequently restored in a more limited form