Smersh,
There are dozens (even hundreds) ways to manipulate the AI in order to create special conditions.
Some of them are more complicated than others but in general you may find more than one specific way to achieve your goal.
For example concerning your type of scenario you could also make use of a special technique that I have developed some time ago and the main concept of it is the "Delaying Beacon".
What is a "delaying beacon"?
Suppose you deploy on the same hex of a clear terrain map an infantry unit and a Armored Car and you also assign on the map several VP flags at intervals/step of 10 hexes (all VP flags will form a straight line).
What will happen then?
Simply the AC will reach all VP flags in very few turns while the infantry unit will only have moved 10-15 hexes.
Do we have a combined movement?
No
So, how can we force the infantry unit and the AC to move in a close formation?
By doing the following map modification:
Suppose that you edit the map and that you change the ground under each VP flag into "IMPASSABLE TERRAIN".
What will happen now?
Once you start the scenario the AC will quickly reach the hex next to the VP flag impassable terrain hex but it won't be able to claim the VP hex so it will stick into that position until one unit with ability to move on impassable terrain will be able to claim that victory hex.
Therefor after 3-4 turns the infantry unit will reach and claim the hex with the victory flag and the Armored Car will be able to proceed to the next VP flag with the infantry unit close following at a distance of three turns (or 10 hexes).
But keep in mind that the above example is just an extremely basic version of the "Delaying Beacon" (the advanced techniques are taking into consideration many game-play parameters).
Also keep in mind that you may achieve the same result by assigning a way-point path with extreme density of way-point marks (2-5 per hex) because this will force the AC to move 3-4 hexes per turn (in the case of an APC the way-point density will even force the vehicle to move 1-2 hexes per turn).
cheers,
Pyros
p.s I advise you to carefully read the details section of the Way-point techniques included in the game manual where you may find some tips concerning the advanced use of way-points.