[komon]

If a, b, c don't compel you, you may do fine with keeping an engineering journal or a personal wiki if all you need is a place to collect your knowledge.

However, to advocate for blogging I've got 2 points:

1. Refining your opinions -- related to becoming a better communicator, I think that forming a cogent opinion post requires you to really think through your thoughts, opinion, and experience on a topic. As a project it can be a great learning exercise, I find that I gain a much more solid understanding once I feel the need to back up my opinions with experience and references.

Which brings me to 2. Learning in public.

Taking the time to write up a good post and share it around exposes you to people who will agree with you, challenge your ideas, and importantly learn from your experience. It's a way to find a community and give back to it, and gain more in return.

Does 1 help you with c? Yes. Is 2 also networking, branding, maybe building a following? Sure, if you try at those parts.

Most the blogs that I want to read care a lot more about concentrating knowledge and experience so they can learn from and help grow others e.g. Julia Evans or Alexis King