Translation:You need to put on your socks.
This is a very special combination and the pieces come together to mean something other than what you might normally expect. tuQ means "to wear something". I would normally expect tuQmoH to mean "to cause someone to wear something". But with tuQmoH it instead means "to make yourself wear something" or rather "to put something on".
Huh? tuQ works exactly like how I'd expect it to work. To "put on (clothes)" is "to cause someone to wear something".
Except that -moH comes with an expectation of causing another to do something rather than causing yourself to do something. You could make the indirect object be someone else with this word, but this word seems to be unique in containing an assumption that if you don't state who the indirect object is then it must be yourself.
What evidence do you have that tuQmoH means "to make yourself wear something"? It means to make someone wear something, and its grammar works in exactly the same way as other -moH verbs.
You're being misled by the English translation. In English, "put your socks on" implies putting them on yourself. In Klingon, tuQmoH does not imply putting clothes on yourself. It means putting clothes on (anyone). paSloghlIj DatuQnISmoH means "put your socks on (an unspecified person)". The context (the fact that it's your socks) then implies that you put them on yourself.
Marc Okrand has said that dictionary entries which are composed of verbs plus suffixes are indeed just the verbs plus the suffixes, and are separate entries only for convenience.
Except that -moH comes with an expectation of causing another to do something rather than causing yourself to do something.
No it doesn't. -moH simply means you're the cause of an action; it doesn't specify who actually did the action.
The use of tuQmoH is exactly the same as the use of ghojmoH. You can ghojmoH a person (HoD vIghojmoH I teach the captain; you're causing the captain to learn something unspecified), or you can ghojmoH a subject (tlhIngan Hol vIghojmoH I teach Klingon; you're causing someone unspecified to learn to speak Klingon). If you want to combine them, you have to make the agent of the sentence the indirect object (HoDvaD tlhIngan Hol vIghojmoH *I teach the captain Klingon, I cause the captain to learn Klingon).
So it goes with tuQ. You can tuQmoH a person (HoD vItuQmoH I dress the captain, I cause the captain to wear something unspecified), or you can ghojmoH clothing (HIp vItuQmoH I dress someone unspecified in a uniform). You can combine them, making the person performing the tuQ into the indirect object (HoDvaD HIp vItuQmoH I dress the captain in the uniform, I cause the captain to wear the uniform).
You get into grammatical trouble when you try to put clothes on yourself, but that's true of both verbs. You don't seem to be able to say tlhIngan Hol vIghoj'eghmoH because -'egh needs a no-object prefix, and you can't say tlhIngan Hol jIghoj'eghmoH because tlhIngan Hol needs a third-person singular object prefix. Likewise with tuQ.
The way you do this is probably to drop the reflexive and migrate yourself to indirect object: jIHvaD HIp vItuQmoH. But I don't know for sure about that. We have no canonical precedent for that.
So the sentence paSloghlIj DatuQnISmoH means You need to cause someone unspecified to wear your socks. I would have no trouble accepting this as You need to put your socks on yourself simply because context would make it abundantly clear. But it doesn't ACTUALLY say that. The English gloss in The Klingon Dictionary can be misleading regarding the true grammar of the Klingon sentence.
I'm really uncomfortable with using -moH to mean that you make yourself do something without explicitly using -'egh or jIHvaD (which are both questionable anyway as you say). But the English gloss definitely seems to indicate that this verb does that, which is why I say it seems to be acting differently. Do we have any other examples where -moH seems to be saying that you make yourself do something?
From TKD 4.2.3:
Adding this suffix to a verb indicates that the subject is causing a change of condition or causing a new condition to come into existence.
There's nothing in the description about causing someone else to do something.
The English gloss for tuQmoH says "put on (clothes)". I think you're reading this as "put on clothes", which in English means "to put clothes on oneself", but the "(clothes)" is just there to disambiguate this from other kinds of "putting on" (weight, music, the lights, etc.). The only canon example using tuQmoH is qogh vItuQmoHHa'pu' (where the -Ha' seems to be in the wrong place) to mean "I've taken off my belt." Note that there's no -'egh.
The only other similar example from Okrand I can think of is X neH yughmoH "include only X", as a command to a computer to filter search results. Arguably, there's an implicit tetlhvaD here. But then, I think there's an implicit SoHvaD with DatuQmoH.
-moH doesn't mean you make yourself do something. It means that the subject causes something to happen. Whether the causer also happens to be the one doing the action is not specified by -moH.
The English gloss says put on (clothes), but that doesn't mean I have to use the exact phrase put on when translating into English. puq vItuQmoH I put (clothes) on the child.** It's a gloss, not a fixed substitution.
Exactly. That's what I am saying. This sentence is somehow indicating that I put the socks on myself, but that's not how -moH works. You normally have to specify that. Like how you specified who it was you were making wear (clothes) in your example sentence. But tuQmoH seems to be able to work with an assumption that if no subject of the main verb is indicated then I am making myself wear the object. -moH doesn't normally seem to do that, but for this word it does.
No, we said context made that clear not -moH. If I said to you, "Your socks are to be put on" there should be no question whatsoever that YOU are going to put the socks on YOURSELF, even though I didn't actually say that. It's because you are likely the one who is going to put on your own socks, not because of the grammar of the sentence.
If you said to me, "You should make your socks be worn," which is closer to what this says, I would certainly wonder if you meant I should put them on myself or if I should be putting them on someone else.
I was illustrating how context can make a meaning plain, not trying to rephrase the sentence.
Just like in English, We're not specifically stating who should have pants put on them when we say "Put some pants on"