From what they said in live letter it seems like the changes they might make as followed:

Heavy Thrust will no longer have it's flank bonus and the dmg dealt +15% will go off even if not at flank

If I"m correct when it comes to "Impulse Drive" the combo only starts if you attack from behind so if you use Impulse Drive in any other direction it won't work meaning it should be easier to use Disembowel.

In a way I can see how they may be aiming to make DRG combos more like MNK and quite honestly I don't see what's wrong with that, in all honesty having to be in a specific spot for the combo to work doesn't make any sense cause what does being in front, to the side or behind a target have to do with the ability to follow through with a combination.

It does appear they are aiming to make the use of positionals as a way to improve damage rather than hinder damage potential by causing DRG to miss out on combos when the mob moves.