> does it require some effort to actually break a compound in smaller parts once it became so common to be de facto a new word of its own ?
Older, well established compounds often deviate a bit from their original meaning over time, those are as opaque as allarme. "Creative" insults (where English also demonstrates a rich pool of compounds) for example will quickly erode from their literal meaning to "generic insult", only the rough position in the universal coordinate system for expletives (general magnitude, position in the spectrum between evil and stupid) remains.
For unknown compounds, there are some that follow standard patterns of known compounds ("Studentenvereinigung" - student union) and new ones can be read as fluently as an expression with blanks ("Studierendenvereinigung" - also student union, but properly gender neutral or "gegendert", "Crowdfundinggründervereinigung" - union of founders who are using crowd funding, hypothetical but would be easy to parse for anyone who has ever heard of kickstarter)
Other compounds however can be rarely used, yet still very much unparsable for much of the population. Take for example the "Backpfeifengesicht" that is cited here a lot, the sub-compound "Backpfeife" (a slap in the face) is strictly regional dialect (or even just local slang, and to make it worse from a time long past) and has been shortened from "Backenpfeife" which would still only make sense if you know what it is. I suspect that it was originally coined as an insider slang term deliberately misleading to outsiders. For those cases, you learn to quickly give up on extracting meaning when it does not work and learn it like any other new word, a meaningless GUID that could be anything, slowly narrowed down any time you encounter it in context. Some parsing may still happen, in the case of the Backpfeifengesicht one might for example infer/suspect that it is not about the face but about a person/type of person, because ending with "-gesicht" is also used in other compounds. For example the "Freibiergesicht", someone who will only grace you with his company when there is free beer (regional, typically used as a very low magnitude friendly provocation)
Older, well established compounds often deviate a bit from their original meaning over time, those are as opaque as allarme. "Creative" insults (where English also demonstrates a rich pool of compounds) for example will quickly erode from their literal meaning to "generic insult", only the rough position in the universal coordinate system for expletives (general magnitude, position in the spectrum between evil and stupid) remains.
For unknown compounds, there are some that follow standard patterns of known compounds ("Studentenvereinigung" - student union) and new ones can be read as fluently as an expression with blanks ("Studierendenvereinigung" - also student union, but properly gender neutral or "gegendert", "Crowdfundinggründervereinigung" - union of founders who are using crowd funding, hypothetical but would be easy to parse for anyone who has ever heard of kickstarter)
Other compounds however can be rarely used, yet still very much unparsable for much of the population. Take for example the "Backpfeifengesicht" that is cited here a lot, the sub-compound "Backpfeife" (a slap in the face) is strictly regional dialect (or even just local slang, and to make it worse from a time long past) and has been shortened from "Backenpfeife" which would still only make sense if you know what it is. I suspect that it was originally coined as an insider slang term deliberately misleading to outsiders. For those cases, you learn to quickly give up on extracting meaning when it does not work and learn it like any other new word, a meaningless GUID that could be anything, slowly narrowed down any time you encounter it in context. Some parsing may still happen, in the case of the Backpfeifengesicht one might for example infer/suspect that it is not about the face but about a person/type of person, because ending with "-gesicht" is also used in other compounds. For example the "Freibiergesicht", someone who will only grace you with his company when there is free beer (regional, typically used as a very low magnitude friendly provocation)