I mix GB at home because I want a mix that stays on the bottom, If it's mixed on the bank it's not inert enough for me. Especially if it includes crushed hemp, a favourite of mine in GB.
Pellets, I don't soak now unless I'm feeder fishing. Feeder pellets are wetted down on the bank.
Feed pellets are coated in oil to make the micros and 4s sink. Spanders I do on the bank.