Spent my best years flying for my national and then headed to Europe. First people that I flew with here were Brit's and boy were they dissapointed when they found that I'd never heard of "altitude checks" every 10,000 feet! In some airlines 5,000 feet! I should've been dead years ago. So should my entire airl;ine have been.
I, quite honestly, still don't place the that much importance in them (even though I now do them) as my colleagues do... Given that the actual clearance and physical dialing in of the altitude are my (and my countrymen's) altitude checks, I find it difficult to see the importance of these (new) altitude checks. (For those who don't know what I'm on about: in some British airlines, each time an aircraft passes an altitude divisible by 10,000 they call out something to the effect of "Passing 20,000 feet for FL350, set, safe and armed").
Well, since we all do these checks, and most are convinced that they are promoting safe flight, I guess that they must be a good thing. Even if all that they do is to keep us talking to each other and ensure that we all (try) to stick to the SOP's. At the end of the day, I personally have learned a great deal more from grey bearded old men with their own little quircks than I have from the SOP that I blindly follow in my daily routine.