Trottoir, Glace, and Billette belong to the passive vocabulary of educated Germans, too. Velo also.

Also the different separator for thousands: 1'000 instead of 1.000

I think your last point that the ß isn't used would be the biggest problem if you want to learn the Standard German spelling of words

@jarnbjo Your observations are right, but I disagree with the conclusion that this poses big difficulties. Almost all of these differences are trivial -- "unless a native speaker knows these words, they will not likely understand what is meant": no na ned. Any literate German speaker will be able to read a Swiss newspaper fluently and interpolate the missing pieces easily (even if they never heard es hat for es gibt, they'll figure it out). It's like saying, "don't read British newspapers, otherwise the Americans won't understand if you say pavement instead of sidewalk".

I practiced German mostly during holidays in Switzerland, so when I asked for a Bankomat in Hamburg I received blank stares :-(

Regarding typography: the use of inwards curved (!) guillemets is incredibly common in print German (that is, print German uses “text »quote« text” instead of “text «quote» text”). Until fairly recently, guillements were in fact vastly more common than elevated quotation marks (“text „quote“ text”) in German print typography. — I’m not sure when that changed.

@gerrit, are you sure you weren’t speaking Swedish? ;)

@phipsgabler My experience is different. Most Germans, even well educated, usually have very little success coping with even the slightest language challenge. I would have expected Germans to in most cases also understand or at least grasp the essence of many Dutch or Scandinavian texts, but the success is usually meager even if the issue is just a vowel shift or difference in spelling. I recently had some 10 Germans look at the following advertisement (in context) without much response: Blikkenslagerarbeider, takrenner, takarbeider, ovnsrør, sveising & reparationer.

@jarnbjo OK, I give you that. There's some truth in that specifically some German nationals will have the unreflected impression that their regiolect is the standard variety of all German, and are much less exposed to others. I can only speak as an Austrian, and we have this diglossia, always (mostly) aware what is regional and what is "formal". This extends to the ability to reflect on the status of Swiss Standard German.

@jarnbjo those first three examples look Dutch but I (as a native speaker) don’t know what they are without context. You might have picked some tough test words. Also, there is no cognate of “tak” in German, regardless of the sense in which it is used.

@phipsgabler There is no doubt that Austrian and Swiss people understand eachother and standard German much better than German people understand the Austrian and Swiss varieteies of the language. The question here was though: Whtat will happen if OP uses a Swiss influenced language in Germany?

@11684 It is Norwegian and all words except reparationer are of Germanic origin and with just a few regular sound shifts perfectly understandable in modern, German language, also 'tak' (btw in Dutch and Frisian: dak). In context, this was a sign on a workshop.

@jarnbjo Then it makes a lot more sense! :-) They sure are some weird words when read in Dutch: “can butcher worker”, “branch runner” and “branch worker”. I was thinking tak/Ast (nl/de), I didn’t realise it was Norwegian (I don’t speak it) in which case the cognate tak/Dach is quite clear.

@11684 Translated segment for segment with its cognates, the first word would be something like blikslaanarbeiden in Dutch. That is obviously not the common term used in modern language, but I would assume that it is understandable? I can at least find the expression in an 1844 dictionary. The German cognate for Dutch 'tak' is btw. 'Zacke'. These words have the same origin, but have evolved into two quite different meanings.

@SwissFrank That isn’t the rule at all. There are lots of non-compound words using “ss” instead of “ß” in Standard German. In fact, “ß” is only used following a long vowel (which is why both “Maße” and “Masse” exist as words, with different meanings and pronunciations). In the old spelling this was more complicated and there was no standard rule for when to use “ß”.

'Abschlägig' is used in 'German German', at least I am familiar with it when a German civil servant writes to me.

You might enjoy looking at Peter Frankenfeld's weather announcement where he takes on the dialects of each region. It is old, and I don't want to dwell on history, I just find the language aspect funny.

@KonradRudolph some older books I own show the exact opposite. That is „quote“ instead of »quote«. In the LaTeX csquotes package the first one is default for german (old spelling) and ngerman (new spelling), followed by guillemets and then swiss, which can be selected as variants. Since LaTeX is really all about good typography, could you substantiate your claim regarding »quote«? I've only seen this widespread in electronic documents (likely for the same reason we often use "quote" instead of „quote“ (i.e. convenience).

@0xC0000022L Some (few!), sure. Most of my German books are currently in storage but all that I have at hand use guillemets. For more evidence, look at Wikipedia or the Duden. For instance, the former says “In der schönen Literatur, etwa im Roman, sind [Guillemets] im deutschsprachigen Raum der Standard.”. I don’t have the latter handy but a Wikipedia footnote cites Duden vol 9, 5th edition as evidence that guillemets are/were the standard in print.

@Janka now I feel pretty uneducated. Trottoir, yes. Glace from French. But Billette? No chance. I'm living only 80 kilometres from the Swiss border. But well, "mir Schwoba kenned älles, außer hochdeutsch" (we Swabian can do anything, except "proper" German), so maybe that's my issue.... Sometimes I listen to Swiss radio, as we receive it here. Last week they talked about the "Velowag". It took me at least a minute to find out, what they were talking about.... Again, with "velo" only known from french, and "wag" pronounced so strange to my German ears I just didn't get it.

Auf alten Fotos von Stadtansichten (Bahnhof, Bus, Straßenbahn) findest du ab und zu Schilder »Billetten«. Die Dinger hießen selbst in Hannover so. Und dass aus der Draisine kurze Zeit später das Velociped wurde, kann man auch wissen. Muss nicht, aber kann.