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-mdynamic-no-pic

i'm curious about -mdynamic-no-pic that's talked about in this article:

Mach-O ABI
<http://www.unsanity.org/archives/000044.php>

in particular:

"the recent [page dated October 21, 2002] update to GCC, the compiler shipped with OSX, allows it to perform so-called -mdynamic-no-pic optimization, which hard-codes the data addresses in the code, so the result is roughly equivalent to the CFM ABI used in Mac OS Classic -- so the GCC itself, compiled with that optimization, is 10% faster. Applications, to take advantage of that, need to be recompiled, so it doesn't affect 80% of the titles already shipped for Mac OS X. Then again, the optimization above only works for executables and not shared libraries."

is this (especially -mdynamic-no-pic) applicable to cocoa app compilation? i guess so. hard-coding the data addresses sounds potentially problematic (clashes of some sort?) to me (i don't have a clue what i'm talking about though), or maybe a step backwards (less dynamism in some way)?

from the gcc manual:

-mdynamic-no-pic
On Darwin and Mac OS X systems, compile code so that
it is not relocatable, but that its external refer-
ences are relocatable. The resulting code is suitable
for applications, but not shared libraries. (APPLE
ONLY)

if compiling an app, -mdynamic-no-pic should be used without question right? and if so why isn't it default? or is it even?
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