In Italy now are 2 p.m, I finished the training with Rop, Makori, Frederick Cherono and Daniel Kirwa Too (4 times 5 km in La Mandria Park on hilly course, recovering 4 min jogging, in 15:06 - 14:37 - 14:45 - 14:50, not for Daniel that ran slower), and, having sent thru e-mail the full training to some friend, I switched on my computer for reading letsrun. So, I saw the poster of the training (probably after your message), that you can see for having more details. But now I want to answer to your questions :
1) This schedule is not only good for a Kenyan, but, you can think it or not, Italian runners train harder. For example, with Italians I use to give big importance to recovery, that preparing marathon is always running, and running fast. My athlete Fabio Rinaldi, winner on 14th of march in Treviso with 2:11:48, ran for example 5 times 5 km recovering 1 km in 15:26 / 3:18 - 15:22 / 3:17 - 15:19 / 3:19 - 15:24 / 3:21 - 15:08 (29 km in 1:29:56). When he trains with my Kenyans in Italy, no Kenyan is able to follow the same training. He kills them DURING RECOVERY. For an African, recovery is recovery. When I gave them my first programs for Kenya, writing for example 4 times 15 min at Marathon Pace recovering 4 min moderate speed, I realized that in 4 min they could run 500m : jogging was jogging. So, Kenyans have always more quality, and training must be different.
2) You can see my answer above. May be that if I find a talented Kenyan able to follow the schedule of an Italian he can run 2:03, not the contrary.
3) In any case, there are many personal differences between one and another athlete, not between a Kenyan and a European athlete. For example, I saw, in December, January and February, during the most important workouts in my different camps, always two athletes in front, in every type of work : Noah Serem and Thomas Kipkosgei. They were the best in 6-8 km tempo run climbing, in 35/38 km, in specific marathon endurance (8 times 8 min. at Mar. Pace recovering 3 min jogging, or 4 times 20 min at MP with the same recovery). So, I told to the manager Gianni Demadonna to find a marathon for them. Serem ran in Vigarano, with another my athlete ALWAYS 4-5 min behind, Pius Maritim. After a split in HM of 68:04, Maritim was able running under 65:00 the second half, winning with 2:13:02, while Serem took 3 min (2:16:06).
The same in Rome with Thomas Kipkosgei. His shape was good for 2:08, and I thought that he could win. Instead, after 33 km his fuel finished, and he run in 2:17:57 (n. 11).
On the contrary, I had athletes never good in training (like the new Joseph Kadon, 34 years old, 2:11:30 in Seville and never fast in training), like already in the past Elijah Korir (2:08:59 at 35 years, with training of poor quality).
What happens ? Some athlete is not sensitive about the energies that he spend in training. Rodgers, for example, is aggressive only some time, when we use a training like test, but normally trains at 90% of his possibilities. He is mentally relaxed, and doesn't use nervous energies in training. He is like Stefano Baldini, never very good in training (never good like Fabio Rinaldi, for example), or Alberico Di Cecco, that are able in training preserving nervous energies. This is an important characteristic, that can bring a good athlete to become a champion.
4) The big difference is in more modulation, with less long run, more recovery and more quality without destroying himself. Of course, before to say that the work of today is better than the work of the past, we must await the results of Boston, that he already won 2 years ago. Last year his problem was of overtraining. This year I want to control the last period, expecially under the nervous point of view. Every comment can be precise after Boston