I think one of the nicest raised bed gardens I ever saw was at a place called Five Mile. It's on the Dalton Highway about 5 miles north of the Yukon River. They also had great tuna salad sandwiches. Surprisingly, no salmon sandwiches.
If you do a control section there is no need to wait with the experiment. I think the more people that do the experiment, the more valid the conclusions we can reach. Different soils, different plants, different conditions all the way around. Could the better results be the result of a better plant and not the soil amendment? Maybe the lesser results were a result of the plant being the runt of the litter. That's where the repeat experiments will prove most useful.
Right now, I don't think it make much difference which amendment is used, although it seems that amending is better than not amending. Ecomin seems to be great for cucumbers but sea90 has the best looking tomato plant so far. I still can't wrap my head around applying salt, even sea salt (sea90), to my garden on a regular basis.