Great conversation... not sure what I can add (but I'll write a novel anyway, lol)... and I have an EM, not a CC. She is still a guardian breed, but maybe not quite as hard-wired (depending on your CC's breeding line). So, just some comments / thoughts for your consideration -
1. The subject is a 10 week old puppy having temper tantrums, just like a human toddler... it might sound like an attack, but it's just an outburst due to frustration, over-stimulation or out-of-calories... at that point, the time-out would be the direction I would go - removing the stimulation, providing a new "job" for the puppy that you can reward (remove the frustration), and/or putting him where he can take a nap. Give him a bully stick to chew and fall asleep with so he can regroup and be ready to be a nice, polite puppy when he re-emerges from his "place". If he won't settle, take him outside (or down the hall) for a quick walk to regroup and bump into a better state of mind, maybe run some obedience commands (anything you can then reward with praise and treats, to push him back into "pack/family" mode)... then back to his "place" for a nap.
2. I am a BIG FAN of the game of tug. Our game has rules! I use tug to teach my dog many things, including "leave it", "drop", "take it", "pull", and Never EVER touch teeth to skin (game is OVER if teeth touch skin, they learn that Quick). The game of tug is FUN!!! It's Interactive, it builds the dog's prey drive (my pups have always been pretty low on that end), it's a great way to burn excess energy and give the dog an "out" for frustrations and zoomies (especially in a confined space where zoomies would be dangerous), it rewards them for biting the RIGHT thing (the tug toy), and for not biting the WRONG thing (your pant leg). The most important thing when playing tug, is to know who CONTROLS the game. Note - The idea is for that to be the human.
The human gets to say when the game starts and when it's over. Ask for the pup to drop the toy, and reward them by giving it back and playing more tug. It is a GREAT game with real world lessons built in! YouTube has some great videos on teaching proper games of tug. If you do find that it makes your puppy more aggressive, too intense or too focused on destroying the tug toy... don't play it. I've never had a puppy that acted that way... but I'm not going to say they don't exist, either!
3. I've never had to use a prong collar on a dog I've had from puppydom. I have used prongs on a rescue dog we adopted... he was "hard of hearing" and ignored any direction on a flat collar or even a slip. I consider the prong safer than a choker (cotton slip or chain link). And it is AMAZING how well dogs "hear" you when they are wearing a prong - very little pressure is needed. But... I would not consider using a prong on a dog under 6 months old... positive methods are soooooo much more effective at that age.
4. Impulse Control! This is a big one that will provide major returns in your life with your dog. Teach "wait" - that was the first command we taught Denna, and it's still our most important and most used. Make your puppy "wait" for dinner, "wait" at doors before going through (in front or behind you, I don't care, as long as they didn't push through without waiting for you to say "ok to go" first!), wait before hopping in or out of the car, wait for anything and everything you can think of. "Wait" means - I know what you want, and I'll give it to you... in a minute. "NO" means - I know what you want and you will NOT be getting it, so quit asking. There is a difference - and the dog will KNOW if you say "wait" and meant "no"... do that too often and "wait" will lose it's value.
5. Mastiffs, EM, CC, DDB, etc, are SMART. They are learning every minute they are awake - what you like, what you don't, what gets your attention, and what you ignore... they will then use that knowledge to get what THEY want... or they will try. They're very good manipulators! Just remember to out-stubborn your pup and you'll be fine! HA!
6. I love all-positive methods for training NEW things... but, I agree with marke, Annette and others (including some professional trainers) - that there are limits. There are situations where negative consequences are required to stop unwanted behaviors. That doesn't mean those negative consequences have to be mean or violent... just perceived by the puppy as something powerful enough to be an incentive for them to NOT want a repeat of that consequence. I also try to make sure the punishment fits the crime. I try to be fair. If the punishment is over the top, the puppy might think he needs to up his "crime" to match the punishment, and that would be a bad thing, all around. Did I mention mastiffs are smart??
7. I love all of BoxerGirl's recommendations. I've followed her posts here on the forum, and have complete confidence in her knowledge and experience in everything dog. She has never steered me wrong.