Yes, as less polygons are seen, the faster the game will run. Though, there's a difference between Hide Object and Hide Object Limb.
Hide Object:
Will hide your object, yes, but it will be like if doesn't exists, so any hierarchy and position won't work correctly, not sure if it's position, but somehow some functions that return values from a hidden object doesn't work.
Hide Object Limb Object, Limb (use 0 for hiding the main object)
This works as the same of above, just that it works correctly with the functions that doesn't with the Hide Object command. Of course, this hides a LIMB, not the COMPLETE object

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-= 933 Mhz - SiS 630/730 8Mb - 128 RAM - 2.1Gb / 6.2Gb HDs - Sound: C-media CMI8738/C3DX PCI - CD-RW 52*32*52 - Windows 2000 =-
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