[plt-scheme] when syntax from one planet package expands to uses from another package

I'm not sure the best way to handle this...

Module "SM" exports syntax "S".
Syntax "S" sometimes expands to code that refers to procedure "P" from 
module "PM".
Modules "SM" and "PM" are coming from two separate PLaneT packages.

Should "SM" merely document that the code that imports "SM" must also 
explicitly import "PM"?
Or should "SM" export all of "PM", and require that any code importing 
"SM" must not explicitly import "PM"?
Or something else (such as renaming PM exports, or exporting wrappers 
around PM exports)?

Thanks,
Neil