Bread vs The Fundamental Techniques of Classic Bread Baking

I have both excellent books: Bread (second edition) by Jeffrey Hamelman and The Fundamental Techniques of Classic Bread Baking by the French Culinary Institute.

Oddly enough: the breads I make from Hamelman turn out te be always a big success. Of course, sometimes after the second try but the work, they turn out well.
My breads from FCI never work... I have the impression the doughs are always too wet. Even when the overall formula is almost identical!

For instance:
Ciabatta with liquid sourdough from CFI has 73% hydration. Also the Ciabatta with a stiff biga has 73% hydration.
I baked both recipes. Of course, it's 2 completely different techniques.

The one from CFI turned out to be flat breads with no holes. The Hamelman version was a lovely ciabatta!!!!

And this is only one example. I have the same problem with other recipes from both books.

Is anyone having the same issue?
Is it because my flower is more or less the same than the one that Hamelman uses but not as absorbing as the one that FCI uses?
I notice that sometimes flowers give different results. I live in Belgium. When I visit my sister in South Africa and I bake bread: I have to use up to 10% more water! (for regular baker's yeast bread).

Some findings or advice would be useful...
Thank you in advance!

Daan.