>>8532114Didn't really look at your pic, something odd and unusual is happening there. The heat could in theory help, but in practice it's unlikely (and for stainless steel it can easily remove the stainless properties). I guess they used a "filler" with an uncommonly different composition. Maybe to help with welding really thick stuff, maybe specifically to help with corrosion resistance in these weak spots, or maybe not all that different after all and it's the sacrificial anode effect (maybe combined with the rust being worn off form the raised weld by people walking around) doing this.
