zoom groom, how much is too much?

Mine get a quick brush every day.  When they are blowing coat, sometimes several times a day.

Is it even POSSIBLE to brush too much??  Especially since the ZG is nice and soft and I would think it can't hurt the skin or coat....

Try having the dog stand, facing you.  Make your fingers into rakes and "rake" from the butt to the shoulders, and also UP the sides.  Good for the skin and coat, won't mean you end up with LESS hair, but might make the brushing stage shorter/more efficient.

 Too much? If you can brush a dog too much, please don't tell Emma. Ena even likes a Zoom Groom, on her naked body, LOL.

Yeah, it's as much a massage tool as a grooming tool. 

Chuffy

Is it even POSSIBLE to brush too much??  Especially since the ZG is nice and soft and I would think it can't hurt the skin or coat....

Depends on the coat type, so yes it's possible.  I no longer use a ZG because (like the Furminator) it breaks and rips off guard hairs and would eventually ruin my dogs' coats.  My friend used her Furminator too much and her GSDs coat looked terrible for a long time.  The nice top coat was all broken and his black saddle looked "salt and pepper".  With our breed, we want those hairs left intact and in good condition.  I show my dog and all I've ever used on him is an undercoat rake, and maybe a simple pin brush to fluff him up a bit.  Everything else I've tried has been too much (the shedding blade did the same thing - ripped off guard hair).  Unlike all these other tools, I can used a shedding rake daily and do no damage to the good coat, I simply quit brushing when I'm not getting anymore undercoat.