I really don't have an educated view on greasing bearings. I know the bearing manufacturers actually have a calculation you can do to figure out the amount of grease you should use based on bearing size. You then have to get a scale and figure out what volume you pump out of your gun.
IIRC Coleman recommends a weekly greasing but I grease my wizards monthly. I try to use a warm ( room temp) grease gun so that it will spread easily. I try not to pump too quickly and allow the time for the grease to migrate inside the bearing. I usually use about five pumps ( pistol grip gun)on the wheel bearings and just two or three pumps for the other ones. I will continue to apply grease to a bearing slowly until all water is displaced. Obviously, it would be better to grease more frequently (weekly)and apply less grease, maybe a couple of pumps. But I'm lazy and not going to bother to do that. I will sacrifice a shorter bearing life for less overall work "hands on" over the course of time. I do have the occasional bearing fail prematurely, but by the time most of my bearings fail it's time to replace the wheel anyway.
Someone here may offer a much more educated view on the subject