You have any kind of nasal drip ? and if NOT? I would still ask Doc about it possibly having to due with sinuses.
I notice that the throat clearing started first , eventually turned into (what felt like a head cold) but turned out to be allergies, so... the Doc thinks for now.
Or, I know for me if I eat large portions, the throat clearing gets really bad.
I havent qiute figured this part out but its excessive(saliva,mucous) accumulating in the throat and seems to get stuck there, along with the nasal drip problem? I believe both play a part in this for me.
Anyways, maybe it'll give you some idea