Heya boys and girls:
Hoping some folks can chime in on whether they're able to reproduce this issue on their system and what I think is the latest version of Edge and OS X Mavericks (versions in video):
Setting a linear gradient with an rgba alpha value of 0.41, 0.39, 0.30, 0.50 all seem to work as expected. 0.40 is the bad mamajama to stay away from. Let me know if any of the steps in the video are confusing. I'm able to reproduce this 100% of the time now... after having spent the greater part of the day figuring out it's quirks... I think I'll just go with 0.39 for now 
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