The Minimal Master is meant to save some time. But if the developers forget to use the right doctype they will end up spending even more hours. While SharePoint will return immediately an error when you skip even one required Content Placeholder, there is no such thing for the doctype. It's definitely about the knowledge and understanding of what you're actually doing.

I always appreciate your posts. Keep them coming!

I agree with you about the DOCTYPE. As a devigner, I am very frustrated with developers just not getting it.

However, I don't see a better alternative for developers than to use a minimal master. Your post title implies it's a bad idea. I think it's really the best way, web developers just need to learn more about web standards.

Using the right doctype is more important than many people think. It's not only a line of code in your Master Page. The doctype defines how the whole page should be processed by a web browser.
The Master Page I use contains a common set of controls we use in every SharePoint WCM project we work on. You could think of it as of an extended version of the community Minimal Master.