What makes it seem implausible is to buy into the concept you need to buy 6 wings and three intakes /engine pods with one presumes three engines as they appear to be tailored to each variant, that then becomes an expensive idea, on top of that, would you want the advanced aggressor trainer cockpit fit in the recon version?
To go from a basic trainer to a greater sweep could that not simply be done by a pivot at the front of the wing and a mechanical bolting system at the rear that would simply be inserted in a different hole to alter the sweep.. Engine power increase could be adjusted by removing a limiter.
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