Help! Antiskate with only a weight...no dial, and she's skating away!

I have a project rpm 10 carbon with 10cc evolution tonearm that has a weight on a string for antiskate. There are three notches on which to attach the string based upon the tracking force range of the cartridge. I currently have an ortofon cadenza bronze tracking at 2.5g and have the antiskate weight in the appropriate notch (according to the Pro-ject manual) from which it hangs. The table is level--checked and adjusted to ensure. The tracking force is at 2.514g (the range for the cadenza is 2.2-2.7 with 2.5 suggested by ortofon) checked with a digital scale (Riverstone Audio digital scale). The soundstage sounds great, vocals are centered, other instruments are placed in space according to the recording... Also the alignment was carefully set up using the WallyTractor and is spot on. 

But sometimes when I lower the stylus to the lead in groove, it will slide very quickly towards the spindle as though no antiskate were present (it doesn’t skip over the record, it falls into the first song groove--and yes I have confirmed that the stylus is present). But it’s a big jump vs just sliding into the groove.

So I found a blank side of an album and lowered the stylus onto the surface and it immediately slid all the way across the surface towards the spindle as though no antiskate were in play. I then disengaged the antiskate weight and experienced the same (expectedly so). But there seemed to be little or no difference between antiskate being engaged/disengaged.

So I engaged the weight again and lowered the stylus, but this time I placed a little extra force on the weight with my finger and was able to get the tonearm to stay in position--applicable antiskate force in play with this extra force. Of course, I have no way of measuring how much extra weight I applied.

The help I need:
Why is the recommended antiskate parameters set by pro-ject seemingly having no effect?
Is something else wrong?
The table and tonearm are obviously manufactured to handle this level of VTF, no?
The tonearm wires don’t appear to be impeding the arm movement.
What can I do to remedy this?
Do I need to do something to remedy this?
I wonder if I’m causing harm to the cantilever with what appears to be no antiskate, yet the music sounds great and the Analogue productions test LP record antiskate tracks "sound" equal to my ears. (But my ears aren’t young anymore, so I don’t think I can place full confidence in that audible test).

Any thoughts, suggestions would be greatly appreciated.