I find that changing my training plan to doing my hard workouts on Tuesday and then again on Wednesday and moving my endurance ride to Thursday or even Friday, sets me up better for hard rides on the weekend. What is the philosophy of separating the two hard days with an endurance effort and shorter recovery going into the weekend?
That’s a totally fine modification. The philosophy of separating the two hard days with a lighter endurance day is to make sure you’re fresh enough to smash your second intensity workout.
However if you find you can do them back to back and it doesn’t compromise either workout then press on. I do something similar by grouping hard trainer rides during the week so I can do longer enjoyable endurance rides during the weekend.
This reminds me of “block training”: By combining consecutively hard works with recovery, you can improve your cycling performance on a variety of levels.