G'day
Everything metal is best kept away from the front of your body while detecting, this is the reason the fibreglass otto type top shafts were introduced as when using large coils the detector could see the top shaft and same goes for any metal objects on the body and boot metals, its believed that because the detector can see these things even at the fringes of the detection field even from the top of the coil, it can de-sensitize the coil and that means some targets will be lost, its also the reason for interference and not being able to get the detector to run as quietly as it should, don't carry your pick on your belt, best to sling it over your shoulder, my 4500 with a 16" nf coil can see my mid sized pick at about chest level not loudly of course but enough to cause some light signal fluctuation, if it can do this then I don't doubt that it would have an effect on the coils sensitivity.
Wearing watches and other jewelry will just cause confusion when trying the locate a target, I don't wear any jewelry at all and often get questioned by the missus why I don't wear my wedding ring, simple answer is I would either lose it or break it, and have not worn a watch for many years as they usually end up broken or left somewhere, so everything like that stays in the car along with the phone as I would not answer it while detecting anyway and you can guarantee the thing will ring if you do carry it about with you and then I would have to stop and remember which pouch or pocket I put the thing in?.
cheers
stayyerAU