It is great that many teams have experimented with various motor saving / sharing techniques over the summer!
Strict power limit of 8 motors in 1 motor increments is one of the best challenges that VRC got to offer for its most inquisitive minded competitors. 
I think, power transmission between drivetrain and tilter might work very well this season, but you have to be cautious which specific differential design to use.
As @Deicer correctly pointed out, the biggest problem with DMD style differentials is that they could introduce a lot of extra friction. Axles of 60T or 84T gears have to continuously rotate transferring your driving power. They also have to carry any force associated with the arms on which the motors are mounted. If those arms twist out of alignment, you end up with double or triple friction cost on the power that flows through the geartrain.
Designs that @1489A and @Anomalocaris have linked above, were used by a number of teams during ITZ and, with a good build quality, worked relatively well for some.
It was easier to do with 393 motors, where not all drive power was going through the differential, and some motors were direct driving the wheels.
For example, most 2131 teams had 4 motors direct driving the robot and only two motors were used on the Mobile Goal lifts, providing extra drivetrain power through the half-sided differential.
Also, 81k had 4 direct drive and 4 differential motors. If you take a closer look at their robot you could also see that motors were not mounted on differential arms and 84T axles did not have to carry extra friction load. Even with reduced friction half of the drivetrain power still had to go through the several extra gears.
With V5 motors it would be very expensive to send all your drivetrain power through the extra gears and axles required for DMD differential. However, there is an alternative solution as animated starting from 0:07 in this video:
When motors are powering drivetrain there is no extra gearing involved, similar to the regular drivetrains. Only when you power secondary function, then entire motor assemblies rotate, which requires some extra gears. An example of such transmission could be seen here: