The real problem with block gaps between different boosters (blocks on the same booster are OK) is that you short the boosters together. The DCC signal is +/- around 0, so whether you short one at a time (staggered) or both at once (aligned) makes little difference. Either way, you will get a current flow because both (all) boosters are referenced to the same ground via the cab bus or control bus. The important thing is to minimize the voltage difference between the two boosters. you do this by measuring the voltage across the booster gap on the SAME rail. This gives a reading of the booster difference. If you lack a meter, you can use a grain of wheat bulb. It does not need to be a good meter, you are not measuring the voltage value, just that they are different. Now adjust the voltage of one of the boosters  such that you have a minimum meter reading or get the bulb as dim as possible.