Say what is true for a TLV too, and cover the to half of the check

docs/decisions.md

@@ -483,24 +483,21 @@ rule and an index of the titles below.
   [#16](https://gitea.larvit.se/larvit/smpp-js/pulls/16). 3.4 calls these fields ASCII, so goal 3
   settles the read alone — its generous clause is scoped to reading, and its sender clause is strict.
   Goal 1 settles the write, being 3.4 as SMSCs actually run it: an operator routing an alphanumeric
-  sender through the upper half is traffic to keep, and Node's `ascii` write already emitted the low
-  octet, so `Kaffeé` went out as `4B 61 66 66 65 E9` before this change and goes out as the same
-  octets after it. Naming the write latin1 is what makes the round trip idempotent, and no peer sees
-  a change. Goal 2 settles the refusals, both of them a `size()` that would have agreed with a
-  `write()` that put something else on the wire: a character past `U+00FF` written as its low octet,
-  and a caller's own `U+0000`, which the peer reads as the end of the field, shifting every mandatory
-  field behind it under a `command_length` that counted the whole string. Goal 4 settles them twice
-  over, since for `一`, `　` and most emoji that low octet is `0x00` and the field went out malformed
-  on the operator's parser. `wantText()` and
-  `wantCstringText()` are the only two places that decide it, which is why the `dest_address` and
+  sender through the upper half is traffic to keep, and Node's `ascii` write already put those octets
+  on the wire, so naming the write latin1 makes the round trip idempotent and no peer sees a change.
+  Goal 2 settles the refusals, both of them a `size()` that would have agreed with a `write()` that
+  put something else on the wire: a character past `U+00FF` written as its low octet, and a caller's
+  own `U+0000`, which a mandatory field's reader takes as the end of the field. Goal 4 settles them
+  twice over: for a great many characters that low octet is `0x00`, and the PDU went out malformed
+  on the operator's parser. `wantText()` and `wantCstringText()` are the only two places that decide
+  it, which is why the `dest_address` and
   `unsuccess_sme` structures write their embedded addresses through `cstring.write()` rather than
   reaching past it into `writeCstring()`. Rejected: reading latin1 and leaving the write spelled
   ASCII, which leaves two halves agreeing only by accident. Rejected: refusing the upper half on send
   to stay strict to 3.4's ASCII, which would be a new restriction taking away traffic this library
-  already sends and operators already accept, on no defect; whether an SMSC wants a non-ASCII sender
-  stays its own call, answered as `ESME_RINVSRCADR`. Rejected:
-  refusing `U+0000` in every text field, which would buy one spelling by taking a legitimate octet
-  away from the length-prefixed Octet String, whose length octet is what ends it.
+  already sends and operators already accept, on no defect. Rejected: refusing `U+0000` in every
+  text field, which would buy one spelling by taking a legitimate octet away from the
+  length-prefixed Octet String, whose length octet is what ends it.
 
 ## The session's life