Why the ten-gun pom-pom was a poor bluff

Was the proposed ten-gun pom-pom an impractical design or a British bluff?

No; it was plausible, and the small difference from an eight-gun mounting gave Britain little reason to bluff about it.

A ten-barrel pom-pom was technically plausible and only a modest step beyond the octuple mounting. Advertising ten barrels would not frighten another navy into a different policy when eight already produced nearly the same effect. Britain gained no clear negotiating advantage from exaggerating such a small difference. The proposal therefore makes more sense as genuine weapons development than as a bluff.