Why don't legionnaires like the VHTA as a melee weapon?

[Sargent Q]

I find that the length doesn't really make a difference as the illustrious is still shorter than the 2 handed weapons and, the VHTA's are as long the the one handed weapons they have.  And they give the option on killing at least some before they get to you. Like Susanoo though its my fighting stye,  I have been playing mount and blade for quite a long while and the earlier versions have a much better stab than the warband one does meaning that i have a very hard time with the stab and it usually gets me killed when i use a one hander with a stab.