It's so funny, I read alot about the TM's being aloof with strangers, but my sheltie is aloof with strangers, that doesn't mean she wants to eat evreryone that comes in the house. LOL
Yeah, TMs are a lot more up front about their aloofness. And they are guardy and independent so their dislike of strangers can be accompanied by warning behaviors. Most people do not understand that warning behaviors are good and they freak out when your giant dog growls or barks.
And they run on a spectrum. Some TMs will not let anyone in your house, and you will need to lock them up when you have visitors. Some are openly friendly to people. Most fall in between, but you don't know where your dog will be until it matures. And being proactive about socializing them in the house helps a lot.
I'm surprised you didn't come across this information. I think the tibetanmastiffinfo site is pretty good at describing what they can be like. A lot of general dog sites just use 'aloof', but I don't think that really covers it. They describe almost all of the mastiff breeds the same, but there are a lot of differences. What they should say is that TMs are happy to be 'aloof' but don't push it. As long as people respect their boundaries, they are fine. But that aloofness turns into overt displays of protectiveness pretty easily.
Strangers, literally, cannot stare at my dog or talk to her without her thinking they need to die. Sometimes she looks like some crazy, non socialized beast. But that's not the case. Like I said, we were very proactive about her socialization. She went somewhere every day and met all kinds of people. And most were dog savvy enough to ask before petting her so it's not like she had bad experiences with new people. Then one day she was done. So we still take her out but when people ask to pet her, we tell them no. She also has a harness with 'DO NOT PET' patches on it. That helps.
Also, do not expect your dog to follow your lead on situations like this. When you read about TMs and they are described as 'independent,' they aren't kidding. These aren't dogs that care about pleasing you. Especially when they think there is some sort of danger.
Also, also, when Athena was young, people were always commenting on how mellow and well-behaved she was. And to outsiders, that's exactly what she looked like. Calm, non-jumpy. Like a really well-trained puppy. I'm talking about 10 weeks and up. She never bounced around playfully like most puppies do with other people. Except kids. She loved kids. Anyway, my point, she looked so mellow because even at that age, she was starting to guard. So her seriousness was just her assessing people. She would just sit and watch everyone, thinking about which ones she would eat when she got bigger.
Keep asking questions. Do you stay in touch with your breeder? The owners of the rest of the litter? All of that is important. Athena was an only puppy, but D'Argo was one of 9. I know what's going on with every puppy in that litter. I keep my breeder updated on D'Argo. She keeps me updated on the other puppies and both parents. We've taken D'Argo to a show to see some of the other puppies and their father. We'll also be going up sometime this fall, I think.
Foster those types of relationships. Knowing about the temperament of the parents and the other puppies will be very useful to you.
I feel like I wrote a book.