PLEASE STOP - CSS tags being removed from version to version

The elements that I'm referring to are any elements that are added for a 
CSS version, then in the next version, taken out.

What about the people that _do_ use the elements? Some people create 
very large sites and use the elements that are available, then when 
those elements are taken out, removed, during the next version - that 
person has to then redesign the entire site, depending on the element used.

I spend quite a bit of time getting work by telling the clients about 
all of the benefits of using CSS.
How do I explain to my client that he needs to fork out another few 
hundred dollars because I need to redesign a site because the element I 
used is now unavailable and that's why his site doesn't "look" like it 
once did?
I surely can't redesign the site on my dime, but it would only seem 
right because I chose to use the tags that someone decided to remove in 
a later version because it wasn't "widely used"...

Just because an element isn't widely used doesn't mean that it isn't 
used at all.

I've read through some manuals that described an element that I thought 
to myself about all the great things I could do with it, just to find 
out that it was taken out because it wasn't used or widely known about 
by enough people.
How does the W3C know how many people are and aren't using an element? 
Just because someone doesn't validate all of their pages doesn't mean 
that they _don't_ use the tags given to them to use.

The W3C provides us with elements that provide great functionality and 
that can be modified and expanded on in the future. I do appreciate that 
and I know many others do, as well. But please do not take away an 
element just because it doesn't "seem" to be being used by many.

Thanks.

Amber.