[Boltman]

Crossing: "Traverses the DEFENSE such that its BUMPERS go fully between the adjacent SHIELDS/GUARDRAIL"

So unless the drone IS the entire robot perimeter with bumpers (16 x 16 worth minimum)
So a drone without all the bumpers would not do anything as no damage or crossing would occur.

If that same drone can score boulders already in opponent courtyard then perhaps its viable (without bumpers)

That could be this years modular:

A main bot with BUMPERS and ability to deliver balls cross defenses and can handle most maybe even the low bar with ball.

A drone that separately fly's over field scoring opponent boulders somehow and can grab other boulders and deliver them to main bot to cross then when on opponent courtyard reacquires the boulders and scores the only defense they cannot cross over is low bar.

At the end it would have to either land on the main body or contact it somehow.

If a team pulls this off cool.