I believe what is being discussed is Gerry's video. He is the owner of a metal detector business, makes very good videos and is a very experienced hunter (IMHO). He does a lot of Nevada gold classes and has an impressive array of finds. In his video he presents a large number of gold rings grouped by their various ID ranges and shows how few you'll miss if you notch out the square tabs. Yes you will miss a few rings, but will the time lost chasing tabs cost you more rings? That is the issue. If you are digging a ton of square tabs it could be a winning strategy. Otherwise, hunt wide open and not risk missing those few rings. To answer the original question would the difference in 505 and 705 notch width matter, I'd say very little. It is a calculated risk that the fine features of the X-Terra make available that very few other machines could offer.