You bring up an interesting point about the variety of methods for defining training zones. While it's true that there's no one-size-fits-all approach, I would argue that using FTP percentages is a solid foundation for any training plan. It's simple, easy to understand, and based on actual data, which is something that can't be said for methods based on subjective feelings.
However, I do understand the desire to individualize training zones further. After all, cycling is a sport that requires a high degree of personalization, and what works for one rider may not work for another. That being said, I would caution against adjusting zones based on factors that aren't backed by scientific evidence. The phase of the moon, for example, has no proven impact on cycling performance, and incorporating such factors into your training plan could lead to disorganization and confusion.
Ultimately, it's important to find a balance between personalization and evidence-based practices. While there may be some value in adjusting training zones based on individual needs, it's crucial to ensure that those adjustments are grounded in scientific research and not just personal whims. So, before you start adjusting your zones based on the position of the stars, make sure you have a solid understanding of the underlying principles and how they apply to your specific situation.