Drawing upon my extensive experience, I'm certain that I'm the ideal candidate for implementing your specific C# sub-routines. For over a decade, I have skillfully navigated the intricacies of .NET and C#, consistently streamlining and optimizing business processes for my clients like yourself. Being proficient in the exact earlier versions mentioned, I am more than capable of creating robust command line applications that'll seamlessly parse command line parameters, log invocations/error messages and write to designated files.
I understand the value of clear and effective logging - it's the key to efficient troubleshooting and maintaining reliability. From your project parameters, it's evident that you require comprehensive logging that tracks not just successful operations but also those ending in errors. I can assure you that I'll incorporate all the necessary features into your sub-routines - from prefixed date and time in ISO8601 format to a completely blank line at starts and relevant logs. Additionally, I can meet the challenge of obscuring passwords judiciously while still providing accurate logging.
This extra facet could be instrumental in case you desire future development or expansion with this project. With my tailored skills coupled with my passion for problem-solving, your 'satin' sub-routine project is sure to end up as elegantly seamless as French silk.