(Why) did the Gyre project fork the URW fonts rather than just extending them?

Question

As I understand it:

During the 1980s, the URW++ foundry created clones of the PostScript Core Font Set and gave those clones the following names:

╔════════════════════════╤══════════════════════╗
║ Original typeface name │ URW++ clone name     ║
╟────────────────────────┼──────────────────────╢
║ ITC Avant Garde Gothic │ URW Gothic L         ║
║ ITC Bookman            │ URW Bookman L        ║
║ Courier                │ Nimbus Mono L        ║
║ Helvetica              │ Nimbus Sans L        ║
║ New Century Schoolbook │ Century Schoolbook L ║
║ Palatino               │ URW Palladio L       ║
║ Symbol                 │ Stan­dard Sym­bols     ║
║ Times                  │ Nimbus Roman No9 L   ║
║ ITC Zapf Chancery      │ URW Chancery L       ║
║ ITC Zapf Dingbats      │ Dingbats             ║
╚════════════════════════╧══════════════════════╝

Those URW++ clones were subsequently re-licensed in 1996 as Type 1 fonts for Ghostscript under the GPL and AGFPL (and in 2009 under the LPPL).

In 2006, the TeX Gyre project was announced, which extended several of the URW++ clones and also gave them new names (thereby effectively forking them):

╔════════════════════════╤══════════════════════╤═══════════════════╗
║ Original typeface name │ URW++ clone name     │ Gyre fork name    ║
╟────────────────────────┼──────────────────────┼───────────────────╢
║ ITC Avant Garde Gothic │ URW Gothic L         │ TeX Gyre Adventor ║
║ ITC Bookman            │ URW Bookman L        │ TeX Gyre Bonum    ║
║ Courier                │ Nimbus Mono L        │ TeX Gyre Cursor   ║
║ Helvetica              │ Nimbus Sans L        │ TeX Gyre Heros    ║
║ New Century Schoolbook │ Century Schoolbook L │ TeX Gyre Schola   ║
║ Palatino               │ URW Palladio L       │ TeX Gyre Pagella  ║
║ Symbol                 │ Stan­dard Sym­bols     │                   ║
║ Times                  │ Nimbus Roman No9 L   │ TeX Gyre Termes   ║
║ ITC Zapf Chancery      │ URW Chancery L       │ TeX Gyre Chorus   ║
║ ITC Zapf Dingbats      │ Dingbats             │                   ║
╚════════════════════════╧══════════════════════╧═══════════════════╝

To explain their decision to use new names for their extended versions of the URW++ clones, the Gyre project leaders said:

Unfortunatelly[sic], the original Adobe names cannot be retained due to copyrights and registered trademarks issues. URW names, on the other hand, are somewhat incongruous. Therefore we decided to coin new names, mnemonic to some extent, consistent within the project.

I would be grateful to know:

1. Whether my understanding (as given above) is correct; and if not, what my mistakes are.
2. Why the Gyre project decided to fork the URW++ clones rather than just extending them under their existing names. The explanation they gave - that the URW++ names were "somewhat incongruous" - is incomprehensible to me, especially since the new names given to the Gyre project's extended versions don't seem to me to be any more "congruous" or memorable than the URW++ names. Bonus points for linking to, and translating if necessary, archived discussion(s) explaining the process by which the decision was reached.

Answer 1

[Summarising comments into a single answer]

The fonts are not simply extensions, so renaming them to avoid confusion is needed. Font names are typically trademarks, meaning they create legal problems, so not using them is advised. It would also be inappropriate to release a metric incompatible font under the same name even if legally allowed as it will simply break existing documentation, and the TeX Gre set don’t retain metric compatibility with URW fonts (at least not as a 'project aim': they allow variation where this is necessary to improve appearance). The 'new' names are also more systematic: all start 'TeX Gyre' and are related to the original names: Avant - Aventure, Bookman - Bonum, Chancery - Chorus, etc.

Of course, for a definitive answer you'd need to ask a member of the TeX Gyre team.