" I think what you are saying is that the sun-absent weather blockage-is always shining the exact same number of hours regardless of whether the clock is changed. I don't think that is true."

You could call 8am by the name "FnoopNurdlee Fobblegrabbit" and the sun would rise and set exactly the same. What your article describes are the imprecise 24 clock we use and also the very gradual changes in orbit, orbital time period, etc. It's why we have a Leap Year. If we could could change the orbital time periods by simply resetting our clocks that would make for a very interesting phenomena indeed.

Obviously the precise time the sun is shining is different for the different times of the year... "seasons"... and each day is slightly different than any other day. Furthermore, as your article attests, every year is a bit different due to slowing down of orbits, rotation speed, etc etc etc. Gravity is always in flux as mass gets further apart, (grand view), and some mass gets closer together.

I read a very interesting article once about where we were 'in the universe' during the many era's. For example: You, all of us, are very far.... billions and billions of miles... from where we were at this exact same 'time' last year. The sun moves around the solar system; the solar system moves through the universe. I'm sure you've heard that -

We are on a collision course with the galaxy Andromeda. This collision, however, will almost entirely be one of gravitational forces and not actual collisions of suns, planets, etc. Simple reason... things are so far apart. Without the effect of gravity the Milky Way could pass right thru Andromeda with nary a single collision of suns and planets. With gravity it's still unlikely.