Endurance.Net Ridecamp Archives

I am concerned about a riding buddy's horse and what she's doing to him. He is a 3 year old Appy gelding who is ridden lightly once, maybe twice a week tops. With the winter months upon us, she's CONVINCED he's lost too much weight and is in horrible shape. She has increased his feed rations over the last couple months so she's up to feeding him in ONE sitting: 3 scoops of sweet feed, 2 of the large coffee cans of soaked beet pulp (totaling 69 oz) and 3 different types of weight gain/muscle builder supplements (totaling 20 oz). Keep in mind, this is south Louisiana. There is no snow, no frozen ground, no iced over water buckets. Our "winter" weather has averaged in the 50's over the last month or so and while the cooler climate depletes some of the pasture foliage, they still have plenty to munch on an hay in addition for a little extra. My friend is having a hissy fit because she is shoving all this crap down the horse's throat and is STILL complaining that he is too skinny, insisting we buy even more hay. Last night the horse took a few handfuls of this concoction she's feeding him and rejected it. So she continued to add more and more feed and various flavored supplements to get him to eat. I'd really like to say something to her about this, but I'm not sure it's my place and I want to get my facts straight before I make alternate suggestions to gorging him with this garbage. 
First of all, is it healthy to feed a horse that many supplements? It strikes me as the equivalent of taking too many vitamins. Second, what's the possibility his gut will rupture by eating too much? Isn't this a colic or founder danger as well? And third, I was under the impression that muscle builders and weight gain supplements should be used in conjunction with exercise. Considering the major gait she rides him at is the walk, doesn't this defeat the purpose of muscle enhancers?

To me, this seems extremely unhealthy. I'd like to tell her something, but she is more my sister's pal then mine, and my sister has discouraged me from opening my "opinionated" mouth because it's her horse and we can't tell her what she can and can't do with him. Do I really have the right to tell her about my concerns or not? The most annoying part about this is the winter has been hardest on my thin-skinned half-Arab.  He's got a coat on him like a grizzly bear's and of the three horses, he's lost the most weight. You can imagine how unsympathetic I have become to her whining about her thick muscled Appy.
What else can I suggest to her "diplomatically" to get her to re-evaluate her feeding regiment? Less quantities of higher protein feed? A vet check? PLEASE ADVISE! This situation has become extremely frustrating.