Glycerol is not a carb bro. It will help hydrate and pull water into muscle cells creating a bigger fuller more pumped effect to muscle similar to slin.
30-45 mins pre get the scoop throw few in mouth drink plenty of water of it. Glycerol needs water as it pulls water into the muscle cell. Get great expansion. Sometimes just use hemavol which has 1g glycerol per Serving
I have a tub of Glycegrow and yeah it do not mix that well. But my intra shake is always made 45min before the gym and 30min in the freezer to make it cold and by that time most of it is mixed.