White Italian gone crazy rooting.

My thought would be to bury it all the way so the roots hairs do not dehydrate and kill it

you can do that or if you have enough root under the soil, the top ones will air prune themselves.

Since it has been rooting a while, would any recommend cutting it off at soil level and planting
a second pant?

Too much humidity.....just leave it alone and those roots will fall off forcing energy to only feed the bottom roots.

Cut it in half and make 2 plants

If it were me, I wouldn't cut it off Mike. You would be dividing the energy reserves left in that cutting. The part that's already in the cup may likely survive as long as there's a bud on there to sprout. But the upper portion would most likely not make it. In trying to to catch up it would likely expend the remaining energy reserves and go caput.

Speaking from personal experience here. I've tried similar experiments with not so good results. Instead, I would second what Dennis said above. Just let it ride.

Thanks to everyone's suggestions. I believe I will let it ride.

You didn't show us any leaf scars.  I've seen this happen when cuttings were accidentally placed upside down  (who, me?  :- )   If it is right side up I would submerge this in warm water to see if there are any roots under the soil.  I would plant it all under the soil diagonally to let all those roots work for you.   So your pot looks like this

|                    |
|     \  <scion  |
|       \            |                          and the whole cutting is under the soil line.
|         \          |
|           \        |
|                    |                    If it's upside down then I don't have to tell you what to do  :)
-----------------

OK Bob, had a change of heart and it is now in a pot like you described above. Thanks for your advice.

This was great insight, Bob!  I had mistaken the top for bottom in a few cuttings, but I fixed, I guess that is not an issue when the entire cutting is under the soil, as the shoots find their way through... I am getting lots of ground shooters now that I got rid of the gnats.

I learned so much here with you all! thank you.

Grasa, if you bury it upside down the shoots will have to grow much longer to reach light than if they were upright. This is because they come out at a fixed angle from the stem pointing down when the cutting is inverted. they will have to loop around to grow up. They may not have the energy to make the trip and even if they do they will always be more vulnerable to breaking.