Can endplates be used to reduce chord length by up to 14%? Can endplates be used to reduce chord length by up to 14%?

I understand large endplates can change the lift distribution from an elliptical one to a uniform one, making the wing more efficient by increasing lift near the wing tips.

This increases the effective aerodynamic span by up to 16% ( see pic below ).

pic: Effect of large endplates on a short span wing, Source: Zenith 



Can this be used to shorten the chord?

eg.

16' span, 2' chord, total wing area: 32 sq ft rectangular wing.

Use large end plate, h/b=20%.

revised effective aerodynamic wing span: 16' x 1.16= 18.5'

Revised chord: 32 sq ft / 18.5 = 1.7' chord.

Is this correct thinking?
It would be possible to do as you suggest.

However the short-chord wing would have to be either thinner and therefore heavier, or less streamlined and therefore less efficient causing higher form drag. Both effects increase induced drag.

The endplate would need to be roughly square in proportion, which would add drag of its own. Also its mass and side area would complicate the aircraft behaviour.

It is generally better to add a small winglet rather than a big flat plate and use it to reduce the wing tip vortex. But even there, a bit extra wing span with suitable washout is just as good.