four foot rapier blades ???

[fernando]

Precisely ... the reach is the issue. The laws legislate on how far you can reach (your foe) with a whole sword and not how long is the blade. Blades may be short and hilts may be long; it is the whole thing that counts for the legislator.
Let me show ou a 'growing' rapier, one in that when in its 'normal' version does not challenge the law but, when you stretch it, it extends up to a seven span sword.
FYI, even Kings (secretly) had them, as you may read in the (left side) caption


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