Is there any harm in keeping the Chrono hand stopped say at the 11 o'clock mark to remind me to watch the NASA's Perseverance Mars rover which is scheduled to touch down on the Red Planet today (Feb. 18) at 3:55 p.m. EST (2055 GMT).

Or if someone wanted the chrono hand out of the way as to not block the dial.

I know some people will run the chrono 24/7 since they want a live center seconds hand but what about keeping the chrono hand stopped?

Running the chrono all the time can cause unneeded wear but what about simply leaving it stopped?

 

Please check out this link in a previous discussion of your concern. The answer is essentially, no.
https://omegaforums.net/threads/not-resetting-the-chronograph.71847/

 

Great quick read. Assuming it's the same with the 3861?

I actually use the chrono often throughout the day for cooking or my lunch break but using it as a marker to remember things is really useful. That's usually how I use a diving bezel.

 

Yes, it is the same.
I usually use my iphone to alert me to things I wish to remember... appointments, phone calls, due dates, birthdays, anniversaries, etc.