I still don't like the current practice of allowing START and END
	parameters to almost every procedures,

I haven't reread srfi-13 lately, but remember coming to the same conclusion.
I think that srfi-13 is valuable even if the parameters remain, but also
predict that they will eventually cause an alternative, somewhat incompatible
SRFI to be created.

That's a good thing.  SRFI-13 is best existing practice and works today.
No SRFI is the last word on its subject.

-t