Wigs, you're wrong! Once again about iterative and incremental development

Probably, anyone who has ever tried to grasp the specifics of different approaches to software development asked questions: what is the difference between iterative and incremental development? Agile - iterative? Is RUP incremental?

Under the cut, the next argument on this topic and the correspondence dispute with Karl Wigs.

In the 3rd edition of Karl Vigers' book, Developing Software Requirements, there is an illustration showing the distribution of effort to work with requirements throughout projects with different development life cycles (SDLCs).

So, the picture separates Agile and iterative approaches. Is this correct?

To begin, we define the terms.

• Iteration - repetition of operations in order to process the results of the previous stage.
• Incrementing - the increment of the results of the previous stage.

Wikipedia prompts :

"Flexible development methodology (eng. Agile software development, agile methods) - a series of software development approaches focused on the use of iterative development ..."

This means that if, within the framework of the sprint in flexible Scrum or iteration in RUP, you rework the results of the previous stage and at the same time implement new parts of the product, your development is both iterative and incremental.
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Below is an image explaining the difference between iterative and incremental development using the example of creating a portrait of Karl Wigs.

Conclusion
Separate flexible and iterative approaches incorrectly. Wigs, you're wrong!