Hi Martin,
I really recommend that you try the low oxygen side by side mini-mash test. Tasting the difference (and witnessing the lighter color with your own eyes) will mean far more to you than a tasting panel p-value.
The test doesn't require any special equipment or ingredients (besides the sodium metabisulfite) and only takes about 2 hours. You can find the tutorial here:
http://forum.germanbrewing.net/viewtopic.php?f=49&t=301
Also, please see my post here:
https://www.homebrewtalk.com/showpost.php?p=7541155&postcount=16
To the OP, in the pdf we talk about various other methods for degassing water that could be employed instead of preboiling. Bubbling CO2 through the water in a packed column is a commonly used method, and I also believe that submersible ultrasonic sonotrodes are a promising approach as well. Check this out:
https://www.hielscher.com/degassing_01.htm