I need some help with "Function" and "ConditionalFilter"

[Dinominant]

here is my script (this is actually my first one :))

#--------------------------------------------------#
LoadPlugin("D:\Installed Programs\AviSynth\plugins\MPEGDecoder.dll")
LoadPlugin("D:\Installed Programs\AviSynth\plugins\Decomb500.dll")

InputFile = ConvertToYUY2(MPEGSource("I:\The Animatrix\VTS_01_1.VOB", 0, "ff"))

#the input file is force filmed and now runs at 23.976 :)

Function IVTCBFF(clip, c)
{
c
AssumeFPS(c, 29.970)
Telecide(order=0, guide=1, gthresh=10.0, post=0)
Decimate(cycle=5, mode=2, quality=3 ,threshold=3.0)
}

Function IVTCTFF(clip, c)
{
c
AssumeFPS(c, 29.970)
Telecide(order=1, guide=1, gthresh=10.0, post=0)
Decimate(cycle=5, mode=2, quality=3, threshold=3.0)
}

ConditionalFilter(InputFile, IVTCBFF(InputFile), InputFile, "Framerate()", "Equals", "29.970")

#Now this says "I see that your movie is not 29.970 fps, so I'll do this: InputFile
#--------------------------------------------------#

my problem is I don't want the line
AssumeFPS(c, 29.970)
in my functions (mostly because they are not needed because if I IVTC something it is obviously going to be 29.970 fps).
But if I remove them, then the net output runs at 19.181. No frames are lost, and the vob isn't IVTC'd, it just runs slower. I am using the latest everything :)

Am I missing something?