Hmm, Ceasar's method sounds like a good way to get bit if used in the wrong hands.
If a dog is growling about something, he/she is uncomfortable in the situation. You need to make them more comfortable.
If they're growling and guarding that means that they're scared their "prize" is going to be stolen from them. You end up reinforcing their fear, if you take it away by force or tease them by sticking your hands in their face or dish.
For an immediate reaction, I would walk away, go find a favorite toy or treat and call the dog over to you. Ask for a sit/down/something and then reward the dog with the toy/treat. If that doesn't work, get the other puppy out of the crate and shut him in it, by himself. He'll want to come out eventually and that's when you can take the bone away and start working on this.
You'll have to take the bones away for awhile or only give them in the crate, one at a time. Then you can start working on this guarding behavior. Start with their kibble(are they kibble or raw fed?). Stand by his dish with a handful of the tastiest treats. Then while he's eating, randomly drop one in every couple of seconds. His behavior will tell you how often you will need to do this; ie days, weeks or months. When he starts getting happy with you being around his kibble and waiting for a treat then you can move to the next step.
Place only a couple pieces of kibble in his dish, when he eats them all and looks up, then you pick up his dish and treat him(YUMMY treats!).. make sure to do both at the same time. Repeat as neccessary. After he gets comfortable with this step you can add more kibble, but pick up the dish before he's done. REMEMBER TO TREAT at the same time.
You want him to learn that he gets GOOD things when he gives up his "prizes".
Then during day to day things, you should keep kibble or treats in your pocket or in an easy to reach place. If the puppy has something he shouldn't, call him over, offer the treat as you say "drop" or "give"(whatever you want). Pretty soon he'll realise that he'll get something tastier or more fun in exchange.
You can also work on this with toys & bones once he is at this point. Call him or walk over to him for his treat, tell him "drop", give him his treat.. then give him the toy/bone back! He learns that "drop" doesn't always mean he never gets it back.
(This method works great for recalls too! Call dog, treat him, then release him back for playtime. They learn that "come" doesn't always mean the end of fun.)
Its a bad idea to get physical with any dogs, giant breeds especially because if they learn that they have to use force to get what they want, they're gonna win, no hands down. If you can get something accomplished by behavior modification, that's usually the safest way to go. Best of luck! I know that it can be trying at times!
~moni