Well, as a hobby writer myself I can say that the writing courses can be both great and horrific, depending on the guys teaching it. It can make you a more effective writer, which is good, but they can also limit your vision, both on grammar and ideas.
For his English texts, being more effective could be great and grammarwise English is very limiting from the start, so that would not be so much a problem as in his German texts.
I see this when comparing (both mine and others) English writing to German writing. English has a SVO corset with a rigid word order, whereas German is both a V2 and OV language with free constituent word order, including unlimited compound words and unlimited extended modifiers.
There is a reason why the current officially longest, correct in grammar, German sentence clocks in at 1077 words. While some might see that as excessive and in German today shorter sentences are encouraged, it is still a sign of learning being able to compose sentences using the full range of grammar features German has. For writing at least, since in spoken German even educated native speakers keep it shorter.
Generally I think going to this course will help Ocean with witing for SG and WIAB, since these courses help with becoming more effective.