Greg,
You should split vft;s when they have produced another bulb. This is
usually by the time the plant has produced 12 leaves or more. I
always find when dividing VFT's, that the new bulbs just fall away from
each other with minimal effort.
As to your plants producing leave with nearly no traps, it sounds to me
like they aren't receiving enough light. Thy should get at least five to six
hours a day of direct sunlight.
Hope this helps,
Russell Elliott
elliott@nexus.edu.au