With regards to gb'ing the Minelab Musky Advantage I've seen it mentioned that the way a certain person ground balances his Musky Advantage is by incorporating his sensitivity into the process, so as to get maximum balance between it and ground balance. Is this critical to depth with this machine? The reason I ask is because I have only performed the ground balance procedure by the instruction book, but I strongly suspect I'm only getting about 6-7" of real depth in ground. Can overdriving the sensitivity affect depth that bad?