it might take more than one person...
If you are trying to satisfy the rate group test, then you need to get the right number of people into the HCEs rate group; enough to get that group to pass. That, to me, is as much art as it is science.
If you are using the ABT, then, I guess you can get one person's EBAR high enough to get the group's average up, but I found that increasing a few people just a little bit might be better than giving one person an out-sized allocation.
(eg: would you rather give one person making $30k a $1,000 contribution or 3 people making that amount $333?)