Ils se sont parlé hier soir au téléphone.

Question

Hello,
I am having trouble understanding why "Ils se sont parlé hier soir au téléphone." is the correct orthography.
Bescherelle explains that there are three cases (https://www.bescherelle.com/faq/comment-accorder-le-participe-passe-dun-verbe-pronominal/):
1. Lorsque le verbe est essentiellement pronominal (c’est-à-dire qu’il se construit toujours avec un pronom réfléchi), le participe passé s’accorde avec le sujet.
2. Lorsque le verbe est occasionnellement pronominal, le participe passé s’accorde avec le COD si celui-ci est placé avant le verbe.
3. Il ne s’accorde pas s’il n’y a pas de COD ou si celui-ci est placé après le verbe.
Obviously case 1 does not apply because parler normally takes a direct object. But everyone seems to put "Ils se sont parlé" into case three. How is "se" not the direct object? They're talking to each other. Why is it "Ils se sont brûlés." but "Ils se sont parlé."? These two seem like they should be in the same category to me. Is it just that "se parler" is a special case, or am I completely misunderstanding?
Sorry if this was already answered somewhere but I haven't found it in my searches if so.
Thank you for your help.

Cécile Janty-Davies · Accepted Answer

Bonjour Bold,
 
Having had more time to reflect on the matter, the verb 'se parler' is an exception to the general rule of agreements with être when here, the past participle doesn't agree with the subject as it has an indirect object pronoun.
parler à quelqu'un
There are about a dozen pronominal verbs whose past participles are 'invariable' because they can't have a direct object complement.
se convenir, se parler, se ressembler, se suffire, se nuire, se plaire, se déplaire, se rire, se survivre, se sourire, se succéder, se complaire, se mentir, s'en vouloir.

Les mois se sont succédé sans apporter de réponse = Months followed each other without bringing any answer
Elle s'est déplu de son nouvel emploi = She disliked her new job
Nous nous sommes plu dans cette ville = We enjoyed ourselves in this town
Ils se sont ressemblé dans leur façon de penser = They resembled each other in their way of thinking 
Elle s'est complu dans son rôle de victime = She took pleasure in her victim role

These errors often catch out educated French people as you have to undergo mental linguistic gymnastics to analyse what the pronoun stands for in grammatical terms.
The case of 'se brûler' is interesting as it normally means to get burnt ( to burn oneself), so reflexive as the subject acts upon themselves as in this example - 
Ils se sont brûlés 
or 
Elles se sont brûlées 
for they got burnt.
But 'se brûler' can have an object as in the case of -
Il s'est brûlé la main = He burnt his hand 
No agreement as the object if after the verb 
I hope this helps!

Alan Graham · Answer

I think the point is that the reflexive pronoun is a COI, not a COD. They're talking to each other.

https://www.lefigaro.fr/langue-francaise/expressions-francaises/2017/07/29/37003-20170729ARTFIG00001-ils-se-sont-parles-ne-faites-plus-la-faute.php

Bold Moon · Answer

Ah I think I might have finally understood thanks to your hint Alan. Someone in the comments of that article dropped this:

>"J'ai appris" suffira.
>Elles ont parlé à elles-mêmes : se = COI, donc : elles se sont parlé.
>Elles ont vu elles-mêmes : se = COD, donc elles se sont vues.
>Tout juste.

Written out like that it makes sense and this agrees with what Bescherelle et al. indicate is the correct form (i.e. "se sont parlé" without an s).

Thanks for your help.