Why French battlecruiser designs deserve attention

Are French battlecruiser designs too speculative to include alongside other unbuilt capital ships?

No; some French proposals were at least as plausible as the unbuilt super-ships commonly explored for other major navies.

French battlecruiser proposals deserve consideration alongside unbuilt super-dreadnoughts and super-ships from other navies. Some French proposals may have had a better chance of construction than the most extreme American, British, Japanese, or German alternatives. Their absence from service does not make them uniquely speculative. Paper designs are more useful when compared by historical plausibility than by the later fame of the navy that proposed them.