Bullseye fine frit

[Lorac]

Can anyone help with advice on fine frit/powder and what temperature it will smooth out??
most recent information I have been give is ...
        ....."Powder will stay matt below about 720 degrees and stay rough below 790 degrees"......

I am a bit confused as I normally use a high contour 780 degrees in my Hobbyfuser 3 and have never had anything still 'rough'?
I am hoping to be able to 'melt in' some fine frit which I mistakenly thought, being such a tiny amount, would 'melt in' during a slump.
Cheers for reading
Grateful for any thoughts!

[Warm Glass UK]

It will start to go glossy at 740C and between 690C and 740C, it will stick but not be smooth.