Are the original forks 700c?
Probably, if the builder's intention was to make it look like this:
BB drop and angles look fine with 650, maybe you need to go to specsavers?
Without the appropriate diagrams to back up your theory, I'm content to disregard it.
@TM started
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Probably, if the builder's intention was to make it look like this:
BB drop and angles look fine with 650, maybe you need to go to specsavers?