> Is relocatable ("dynamic") code just as efficient as absolute code?

Depends on what you call "efficiency". Here is a short list:
1) Relocatable code, in its basic form, is apt to add additional code
for bank switching and page switching. Code will therefore generally
be longer and slightly slower. However, most of this can be mostly
prevented with good macros, proper grouping and a good linker script.
2) Relocatable code can allow local variables, which, if you don't
have a proper design in advance, means that you will be much more
flexible in reusing registers. This increases the amount of registers
that you would have available.
3) Relocatable code makes it easier for the code writer to reuse code,
and can increase development speed considerably (lots of efficiency
there).
4) Relocatable code makes it easier to move code from one PICmicro to
another PICmicro, which means that if you don't have a proper design
in advance, you can easily migrate to something more suitable for your
application.
5) Relocatable code is not more difficult to write than absolute code.
In the beginning you can use a linker script from Microchip, once you
understand the concepts you can use more efficient methods (with no
need to rewrite your code).

I'm sure others will add more items to this list. In my life so far I
have discovered only one application that required absolute code, and
that was just a crazy attempt at scraping all the performance I could
out of a 16F628A, which is not something I'd recommend to anyone
(moving to an 18F would be a much saner solution).

Greetings,
Maarten Hofman.

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