Impact of Hydroxyethyl cellulose & when to add

I made a basic emulsion with Vegetal/Montanov68, glyceryl oleate, sunflower oil and water with and without incorporating HEC into the water phase. I found the emulsion without HEC was actually thicker after initial cool down although the batch with HEC has thickened up over time (5-6 hrs, but doesn't reach the same thickness as the batch without HEC - at least so far). Does this sound odd to anyone? Logically I would have thought the batch with HEC would be thicker than the one without. My suspicion was that the gelled water was making emulsification more difficult hence the lower viscosity but adding it post emulsification just doesn't seem right. I am using HEC at 0.4%

Also there seems to be numerous takes on when to add the HEC. For this test batch I have hydrated in the water phase and stirred until it gels the water. I've then combined the phases and homogenised. However some people seem to recommend only adding HEC to half the water phase and emulsifying with the other half first then adding the solution with HEC. Others seem to recommend emulsifying with a straight water phase and then adding the some HEC gel after emulsification. If the goal is to thicken the external phase (water) then logically it would seem to make sense to add the HEC to the full water phase so it can thicken it all. Is this deemed to be the universally correct approach or has anyone had more success with alternative approaches. 
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