Why the limited use of templates?

[Reiner Pope]

I wonder why many of the functions in Phobos aren't templated. For 
instance, the std.math functions could benefit from the user being able 
to specify the type used, to avoid unnecessarily precise calculations. 
Also, there's the same issue with std.string.

And in a more general view, templates are nice because of the duck 
typing (or structural typing) that they allow. I was thinking about 
creating a string substitute class in D, but doing so would require 
redefining the std.string functions, whereas templated versions of those 
functions would be satisfied if I just duplicated all the required methods.

I'm not asking so that I can point out this code and say 'haha, that's 
not being done properly,' but I'm actually wondering what the reasons 
are. I think perhaps they are:
1. They were written at a time when D had an ugly template syntax.
2. Using templates requires the source code to compile instead of just 
linking to the library files.

Any thoughts?

Are there reasons why phobos shouldn't be changed to support templated 
versions of these functions?

Cheers,

Reiner