spec: Not all countries require proof of ID when buying SIMs
diff --git a/docs/imsi-pseudo-spec.adoc b/docs/imsi-pseudo-spec.adoc
index de178b0..e132a54 100644
--- a/docs/imsi-pseudo-spec.adoc
+++ b/docs/imsi-pseudo-spec.adoc
@@ -6,12 +6,11 @@
A long-standing issue in the 3GPP specifications is, that mobile phones and
other mobile equipment (ME) have to send the International Mobile Subscriber
-Identity (IMSI) unencrypted over the air. Each IMSI is uniquely identifying the
-person who bought the associated Subscriber Identity Module (SIM) used in the
-ME. Therefore most people can be uniquely identified by recording the IMSI that
-their ME is sending. Efforts are made in the 2G and above specifications to
-send the IMSI less often, by using the Temporary Mobile Subscriber Identity
-(TMSI) where possible.
+Identity (IMSI) unencrypted over the air. Each IMSI is a unique identifier for
+the subscriber Therefore most people can be uniquely identified by recording the
+IMSI that their ME is sending. The 3GPP specifications provide means for
+implementations to send the IMSI less often by using the Temporary Mobile
+Subscriber Identity (TMSI) where possible.
But this is not enough. So-called IMSI catchers were invented and are used to
not only record IMSIs when they have to be sent. But also to force ME to send