Can platooning effects be modelled?

Yes, it is possible.

Definition one: group of cars (known as a 'platoon') the size of which is defined by the signal times.
These platooning effects can be generated by:
- modelling the adjacent junctions (platoons formed by signals)
- lengthening incoming links (platoons formed by car-following and different desired speeds).

Definition two: Grouping vehicles into platoons is a method of increasing the capacity of roads. An automated highway system is a proposed technology for doing this.
This ca be simulated using scripts, see the example Platooning.inpx in ...Examples Training\Autonomous Vehicles (AV)\Platooning.COM (since Vissim 9). In the future PTV Vissim version also integrated funcionality may be inplemented (without the need for scripts).