Wavetable Shape Mod seems to work differently than explained in manual

[interruptor]

Hi all.. 
The manual says on p.17:
„For the wavetable shapes, Shape  Mod/Pulse  Width  crossfades between the selected shape and the  Wave Left and  Wave Right selections. Let’s say, for example, that the selected wave shape is Mellow,  Wave Left is set to  Tines, and  Wave Right is set to Nasal.  A Shape  mod/pulSe  width setting of -64 will be the  Tines wave, 0 will be Mellow, and +63 will be Nasal.  Values between -64 and 0 will be a mix of  Tines and Mellow; values between 0 and +63 will be a mix of Mellow and Nasal. “
Actually the -64 setting does not sound like Tines but rather like something in between Tines and Mellow. The same applies for other combinations as well.
I find that somewhat strange because it is not possible to completely transition between two wave shapes.
Is this a bug or a feature?

Best regards   

[interruptor]

To further explain what I mean I followed the example given in the manual excerpt and recorded the outcome.

Setup:
- Start with Basic Program (buttons Latch + Hold)
- Set OSC 1 to shape "Mellow"
- Waves Left = "Tines", Waves Right = "Nasal"

In the recording linked below you can hear the following:

1. Waveshape "Mellow", Shape Mod = 0
2. Waveshape "Tines", Shape Mod = 0
3. Waveshape "Mellow", then slowly moving the Shape Mod control to -64 ==> This should result in the "Tines" shape. But it sounds different. The funny thing is, that the waveshape display actually shows the "Tines" shape, but the sound is different.

4. Three reptitions of the actual Tines shape and the shape resulting from moving the Shape Mod to -64

http://www.interruptor.ch/PRO-2_wavetables_-_Mellow_vs_Tines.mp3


Also I attach screenshots from my DAW to compare the two different waveshapes.
Left side of pic: "Tines"
Right side of pic: "Tines" assigned to "WAVE LEFT",  Shape Mod = -64"
http://www.interruptor.ch/PRO-2_wavetables_-_Tines.png

I searched the forum and also looked at reviews of the Pro-2. Nobody seems to have bumped unto this. I am surprised nobody is bothered by this, since it means that you cannot transition completely from one waveshape to another.
Want to create a sequence with the pure "Ohhhh" and "Ahhh" waveshapes? Not happening on the Pro-2 unless you assign these two shapes to two different oscillators and crossfade between the oscillators using the mod matrix..