If I remember correctly, CoHO used vCoH doctrines.
They did not.
CoHO is the innovative system of CoH2 "Commander", where you can customize each ability and choose which one you like most. You can even concentrate on maximize effectiveness of a single ability, but will cost you other ones.
And each ability of CoHO is distinguished to each other. True, it takes idea from CoH1 ability, but with addition.
For example, in CoH, you can call King Tiger with 2K HP once. In CoHO, you can do the same, but only with 1K Hp. You can then improve it back to 2K HP, and even more, you can re-call another King Tiger with 50%/25% penalty mp depend on how much points you spend on the ability. Some of the points will give King Tiger the ability, like the one to suppress infantry near it.
Or US AT Gun, normally, it would drop a single atgun, but you can upgrade the ability to deploy Anti-tank airborne that can throw atgrenade and deploy tank trap, to force enemy tank into your kill-zone.
There are many unique abilities. My most favourite is "Black out", which rotate, blur and color-blind both your team and your enemy's minimap. Or "Decoy drop", which drop decoy to confuse enemy auto-fire, especially in the heat of battle.