A Guerre de Course strategy (aka raiding) is an admission by the nation using it that they cannot compete at sea with their opponent. It is a spoiler rather than a winning strategy.
It's not a question of admitting anything. Either a country can or can not challenge for naval superiority directly, and if it cannot, then concentration for decisive battle is entirely pointless and the options become dispersion (commerce warfare) or inactivity.
In WW 1 the German's best course of action given the size of their fleet relative to that of Britain was simply to engage the RN and accept a war of attrition. The RN cannot afford to lose at sea. Britain is a sea power and will have to accept battle to retain control of the sea.
During the age of sail the fleets of the outclassed Empires, such as was Germany's position in WW1, did not seek out and engage the Royal Navy, because that would be suicide. Rather, they operated to continue vital trade with their overseas possessions, attempting to slip by the RN, (for example, the annual Spanish silver convoys from the Americas, trying to cross the Atlantic to Spain without being intercepted).
Similarly, for Germany in WW1, one useful activity would have been the continued import of high-value low-tonnage commodities such as rubber, nitrates, etc. (It doesn't even have to get to Germany, it has to get to Norway, then the material can cross to Germany via the Baltic or Denmark).
For Germany, a fleet in being sitting at anchor is nothing but a waste. Germany is a land power. Their having a sizable fleet that is at least competitive with the British would indicate that they should use it and even use it up.
Yes.
Now, if Germany didn't build a large fleet in the years prior to WW 1 their best course would be the Guerre de Course and put considerably more effort into building up their army. A defeat of France in 1914 rather than a stalemate pretty much ends WW 1 before it begins. Germany could then turn East and take out Russia.
I think a case can be made for a smaller fleet with the savings used to fortify the western frontier (including along the Belgian border), to neutralize the French army and allow the bulk of the German army to concentrate with the Austrian on taking out Russia.
That leaves Britain without means to pursue the war other than by blockade.
Yes, if Britain had one or no continental swords remaining, her war effort fails. Germany's path to victory was therefore to pick off Britain's allies one by one on the continent, while Britain's was to keep the pressure on Germany's coalition with as many partners on as many fronts as possible.