Does splitting long endurance rides really affect the training effect of the rides? Does splitting long endurance rides really affect the training effect?

It's quite often not recommended to split the rides even though the total duration is the same. 

Here are two examples. Assume that they exercise at the same endurance pace.

Athlete 1


M 30 min at 8:30 AM, 30 min at 5:00 PM
T 30 min at 8:30 AM, 30 min at 5:00 PM
W 30 min at 8:30 AM, 30 min at 5:00 PM
T 30 min at 8:30 AM, 30 min at 5:00 PM
F 30 min at 8:30 AM, 30 min at 5:00 PM


Total duration: 5 hours

Athlete 2


M 90 min at 8:30 AM
W 90 min at 8:30 AM
F 120 min at 8:30 AM


Total duration: 5 hours

Notice that the duration is the same.

Why longer but fewer sessions may be better

According to this article, having the workout done all in one go is more important for those who are well conditioned because recovery is faster.
http://www.intelligent-triathlon-training.com/-splitting-long-training-rides-.html

Fatigue increases RPE which may suggest an increase of muscle fibre recruitment. Recruiting more muscle fibres should mean that they produce more capillaries and mitochondria. It makes sense why running slower but longer can make athletes get faster. If the slow twitch muscles are refuelled during the 8 hours rest like between commutes, the fast twitch muscles may not get exercised because there wouldn't be a need to.

Does that work in real life? In real life, would athlete 1 be more likely to plateau sooner? Maybe experience sooner cardiac drifts during a longer workout or race?

Possible contradiction

According to some articles, it's ok to split up workouts.

https://www.sharecare.com/health/types-exercise/do-daily-exercise-at-once

https://abcnews.go.com/Health/story?id=118017&amp;page=1
"Long" is subjective but those aren't really endurance training sessions. The 30 minute sessions could be completed on glycogen stores alone, and at least the 90 minute sessions after a decent breakfast. One way of thinking of endurance rides (events if you're thinking tri) is those where fuelling during the ride becomes important. 

But there's a massive gap between general fitness advice for the unfit, as you've linked at the end, and training for competition or other challenges, as you've linked earlier. To me you've described athlete A's habit (or even commute) , and athlete B's training plan, as you say the pace is the same and an endurance pace.