I disagree with you. But I won't say "you are wrong", because there is no objective reality here

You say you are disagreeing with me; implying by the dint of what you quoted, that what you are disagreeing with, is my interpretation of Royce.

But it is not my interpretation, but rather the general interpretation of:

1. Royce:

   From wikipedia, which whilst not definitive, has sufficient openness to cross-examination, to avoid major single-sourced opinion errors which says:

   In Royce's original waterfall model, the following phases are followed in order:

   • Requirements specification
   • Design
   • Construction (AKA implementation or coding)
   • Integration
   • Testing and debugging (AKA Validation)
   • Installation
   • Maintenance

   Thus the waterfall model maintains that one should move to a phase only when its preceding phase is completed and perfected. However, there are various modified waterfall models (including Royce's final model) that may include slight or major variations on this process.

2. The obvious, common-sense interpretation of the term Waterfall Model:

   From Hutchinson Concise Encyclopedic Dictionary: 'Waterfall': a stream or river flowing over a steep precipice.

   Water does not flow uphill; the waterfall model does not iterate.

The fact that you cannot test until you have some code; and cannot code until you have some design; cannot design until you have some requirements; means that any methodology has to show those steps being started in the same order as listed above.

The single thing that distinguishes the waterfall model, from all other models, is the absence of feedback loops and iterative processes. The moment you add any kind of feedback or looping; the waterfall analogy is broken and you are talking of a different model.

It is not -- cannot be -- a modified waterfall model once you add feedback and iteration.