Before explaining the benefits of writing, let me make one thing clear - writing alone will not help you become a professional investor or trader. If that was true, the best portfolio managers would have been journalists from FT, and WSJ. However, writing about finance helps me in many ways.
Thinking about a topic
As much as I try, I do not enjoy writing about topics I do not care about. Most of the topics I cover in my post are the Indian economy, Crypto (mostly bitcoin) trades, Global macro, and limited financial news. If I exclude financial news from the above list, then I am left with a limited number of topics to cover. I am also trying to write one post a day. So in order to write a post daily, I need to think about various aspects of crypto, global macro, and the Indian economy to make a meaningful post. This helps me to think about various aspects that I would otherwise not read about, due to paucity of time or sheer laziness. The first step to make an investment is to have a big picture view of things. Blogging has definitely helped me do that.
Research
I will not say that my posts are extremely detailed or similar to a research report. Preparing a research report requires weeks, if not months of analysis. Moreover, it requires tools that I simply cannot afford without being a professional investor or working at an investment desk. However, posts about the Indian economy or global macro require that I read regularly about these topics, watch interviews, read public available research, and more. While writing the post, I often end up searching for multiples data points to make an argument. Sometimes I find very useful tools that will help me with data or introduce me to risks or views I had not considered. Research for a post definitely helps me become more knowledgeable in general.
Keeping a track record
It is quite easy to formulate a view or recommend something. However, it's quite the opposite to build a track record. More than success, failure helps in becoming a better investor. When I proclaim something in my posts, it will meaningless to me unless I check whether my decisions actually turned out to be right or not. Simply drawing lines and saying I will buy the dip at some level on a chart if not useful. Staying out of the market due to a cautionary view can lead to opportunity loss. The whole goal of learning about finance or investing is to become better at it. This is one field where improvement has direct and positive monetary consequences. Blogging definitely helps me go back to posts and know how often I am going wrong, find reasons for that mistake and try and not repeat those mistakes in the future.
There is a reason why most portfolio managers start as investment analysts and then move on to become portfolio risk managers or asset allocators. Superior idea generation and research help build a track record that eventually separates a good investor from sheep. If you are not a professional, writing can definitely help you think in detail and hone your investing skills.