You make it sound like schools that don't do their own lab work don't even teach you anything about it, as if they leave it to the imagination. Not quite....
As far as anatomy goes, if you know your morphology, you don't have to actually make the crown to tell if it is correct in dimensions. As far as occlusion goes, it is easy to check and no school leaves you hanging as far as how to adjust occlusion where it is adjustable. As far as opacity/translucence/color, you don't have to make 100 Empress II's before you know what #9 should look like. Shade matching too, is not that difficult at all. Really, the important thing is being able to effectively communicate to your lab how the tooth should look and then to be able to point out errors in how those instructions were carried out. Dental school teaches you how each technique works, and each school DOES go through the sequence of working up models, etc., but some schools make you go through needless repetition of tasks that benefit you in no way, though the understanding of how they work is essential. In today's dental world, NO dentist does their own lab work because it just isn't cost effective in any way, therefore it doesn't make sense to train to be a lab tech.
It IS like working on cars. I have worked on them before and know how to perform all essential maintenance tasks as well as how to diagnose most serious problems with the car...however that does not mean that I need to operate the 4-wheel alignment machine myself, that I can leave to the mechanic, who specializes in that detail area. If you know what castor, camber, toe-in and out are yourself and you know what the mechanic does to achieve the results you want in these various settings, then you don't have to actually do the work yourself, but only how to diagnose what the problem is (if any) when you get it back from the shop.
Dentistry is all about a balance of doing the detail work yourself where it is needed and knowing when to delegate those details out. Knowing how the procedure is done and going through the process is one thing; training as if you would do it yourself just doesn't translate to real life.
But we digress...I don't want to totally hijack this thread.