For those who have a NYTimes subscription, here’s a good article about a guy who is a “professional” pacer/rabbit for many of the world top elite.
Meet the Runner Who Leads Every Pack and Then Vanishes https://nyti.ms/3KCDR8V
As @patrickmilano and @bellaburda and @jullfly and @Mikhail_Kern can attest, rabbiting is a lot harder than it looks since it’s a dance between setting the perfect pace (and holding it) and helping the runners along. Sometimes, as Henry Williams ran into this year in the Elite 1 heat at Hartshorne, the rabbit runs the requested pace, but the runners don’t keep up, leaving the rabbit in a quandary—should they stick with the requested pace (generally not) or fall back and pick up the runners again and try to coax them back to pace (usually).