By way of background, only about 2% of federal criminal cases go to trial.
Trials are rare in the federal criminal justice system: Just 2% of criminal defendants went to trial in fiscal 2018. Acquittals are even rarer.
www.pewresearch.org
But the conviction rate is 83% for the cases that do go to trial.
>>>Put another way, only 320 of 79,704 total federal defendants – fewer than 1% – went to trial and won their cases, at least in the form of an acquittal . . .<<<
The odds of a conviction and many years in prison are typically too much for a defendant to risk. Trump appears to be h*ll-bent on going to trial, so this case is probably an outlier just on that basis (I'm under the impression that Trump doesn't realize how poor his odds are).
I don't know what percentage of the 2% result in a directed verdict. My understanding is that it's not that unusual. However, this is a highly unusual case to begin with, and there's really no way to predict the chances of a directed verdict in this case based on a typical federal criminal case. It would be pure guesswork at this point.
It might be possible to make a somewhat better guess after all of the evidence is of record, but it would still be a guess.