Coincidence? 4-5 days after each release a forking situation?

One user asks here:

• "Is it common for other coins to have fork "situations" once a week or is that unique to Gridcoin?"

Well, see e.g.

• "Forks happen all the time, you could say with every new block. With every cryptocoin that is out there, and the clients notice this soon and bring you back on track."

and more in the prelude here.

But...
I looked at the data (since we have since >4 weeks superblock troubles) (link on steemit) and saw this:

• 4-5 days after the new releases (3.5.9.4 and 3.5.9.2) we had a fork: (L) + (G)
• which we successfully coordinated in the IRC channels with the people being on the fork
• I also noticed, though: that the "self-healing" of the client in fork situations did NOT work :-( People were for >1h and >3h on the fork still.

(link to image)

I'm wondering if this is just bad luck or another factor?

• e.g. some events on/before weekends (since it happened on a Friday + Saturday)? 
• shortly releasing each time before a version (see (RT) below)? 
• would a mandatory version have helped? (see here and article)
• ...

What other things could have played a role?
I provided data about the fork (G) to 2 devs, see here, and it is being investigated.

Recent Gridcoin forks:

• July 21, Friday: Gridcoin: fork situation about 3h ago
• July 8, Saturday: Did we save the world yesterday? Maybe, perhaps, who knows...

Release times (RT) of:

• 3.5.9.3: released 17.5h before 3.5.9.4
• 3.5.9.1: 27h before 3.5.9.2

tags:
gridcoin beyondbitcoin blockchain fork forking