Ive just caught 20 Macks in less than an hour on Shoreham arm,There were a fair few caught whilst i was there and the weed was not a problem at all,just some stringy stuff on the hooks and leader knot occasionally.
Although there were some big ol rafts of weed floating around it is avoidable.
I looked at the beach first and the amount of weed washed up is amazing.
I didnt see anyone on the East arm so i think thats where i will be this Fri/Sat.
Good luck AdurPeanut and i hope the info helps.