HD should not be affected... that is recorded directly from the stream and is not encoded in any way.
Analog, on the other hand should see the improvement as described, but based on the "tweak" I'd think it's for live TV only. Changing the profiles for recording quality (good, better, best) would more likely improve the scheduled recording, but I'm only speculating on that -- I'm not aware of the keys to change.
That being said, I'd expect the buffer file size to increase if that value is increased.
Vista Ultimate 64-bit SP1
Asus M2A-VM HDMI
AMD Athlon 64 X2 5200+ (65W)
500GB SATA HDD; 4GB (2x2GB) DDR2 800 SDRAM
nMEDIAPC HTPC 500BAR
Samsung 20X DVD±R
HD HomeRun; nVidia DualTV
Linksys DMA2100; WRT600N Router
ZALMAN CNPS 8700 NT