A normal day at a Japanese SIer, explained as politely as I can

Good evening. Several members asked me in the comments what a "normal day" is like at a Japanese system integrator (we say SIer). I will try to explain honestly. I am sorry for my poor English and for the length. I wrote it on the train.

1. 7:40 I take the train from my home in Sakai to the office in Umeda. It is crowded, but it is very punctual. The train is the most reliable system in my life, I think.
2. 8:45 Chōrei (morning meeting). Our section stands up and one person gives a short speech. Last Monday it was my turn. I talked about hydrangeas, because it is the rainy season. Nobody asked about the project. This is normal.
3. 9:00 to 12:00 I work on the migration of a regional bank's system from COBOL to Java. The COBOL was written in 1989. Many lines of the new Java look like the COBOL, but with semicolons. I am not proud of this, but the customer's requirement is "same behaviour, exactly", including two bugs that their branches depend on.
4. 12:00 Lunch, bento at my desk. At 12:00 the lights on our floor are turned off to save electricity. We eat in the dark. Visitors find it strange. We do not notice any more.
5. 13:00 to 17:30 Design documents. Our design documents are in Excel. Each cell is a small square, and we use the cells like graph paper to draw screens and tables. If there is a screenshot, we paste it into the Excel. One design document I maintain is 41 sheets and 38 MB. When I explain this to foreign engineers, they think I am joking. I am not joking.
6. Approval When a document is finished, it needs approval stamps (hanko) from my leader, his leader, and the customer side leader. Now the stamp is often digital, an image of a red circle in the corner of the Excel. The image of the stamp is approved, but nobody reads sheet 27. I know this because there was a mistake on sheet 27 for eight months.
7. 17:30 Official end of work. Nobody leaves. Leaving first is... how to say... a small courage.
8. Wednesday Wednesday is "no overtime day". We are encouraged to leave at 17:30. Many people leave at 17:30, go to a cafe, and continue working on their laptop. I do not think this is what the HR department intended.
9. Friday Sometimes nomikai (drinking party) with the section. Attendance is not required. Attendance is also not optional. I drink oolong tea and listen to my manager's stories about the 1990s, which are actually quite interesting.
10. 21:30 Train home. I study English or read this website. Thank you for making my commute educational.

Some things I want to say so you do not misunderstand. My colleagues are kind and very careful people. Our systems run for decades because we are careful. The bank I work for has not had a major outage in my eleven years on the project. But I think sometimes we are careful about the wrong things, like the colour of the stamp, and not careful enough about the right things, like automated testing. Our regression test is an Excel with 2,300 rows that two people execute by hand for three weeks.

If I may ask one question to the members: in your company, who reads the design document after it is approved? I am curious if this is only a Japanese problem.

Thank you very much for reading.