My experience is that matching is everything. When you have the matching perfect you may be able to see the difference between various profiles and I would expect a scientific profile to be better than a hand carved thing, but you will never see any difference until you have mppt tracking.
Changes in blades do alter the characteristics and if you load at random you will find some blades work better than others. The wider tapered and twisted ones will probably work better in stall mode, the Jakes and the parallel untwisted profiles will need to "get away" at the top end to work properly. Jacobs managed to get the loading fairly good considering the technology available and they spent a lot of time on their dynamo design, using field saturation and various other tricks to get an optimum load.
Wincharger did virtually no generator design but may have played around with different blade profiles to suit what they had.
Dan has a point about a tame and reliable machine, I have believed for a long time that these machines survive more by stall control than furling and a blade that stalls out harder is less likely to pull through stall in a storm and burn the thing out.
If you tweak the thing to run clear of stall the high wind performance will be an order of magnitude better but you will really have to get it to furl reliably.
For small machines I see no justification for running stalled with poor performance but with things above about 14ft most people have enough power not to need the high wind output and a safe and quiet machine that does what you need without going frantic has a lot to be said for it at least for battery charging. For grid tie or heating then it's a different story.
Flux
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