From speaking with Tim, I had the impression that he would be ready for the doors in about a week or ten days when they would be delivered.  I spoke at length with him about his plans, and he threatened not to come back if in the meantime he found another job. He told me the floors were so smooth, they might not even need (much) sanding before being treated with polyurethane. He pointed out to me that he cannot finish installing the floors until after the spiral stairs are in place.

In the light of your opinion as I understood it, that Tim should not be delayed, I ordered the doors as Tim requested. They will be in the way of sanding and finishing the floors before they are installed and they will be in the way of sanding and finishing the floors after they are installed, -  but we have the option of asking delivery be delayed until the floors have been properly finished and take our chance on Tim's availability. I have reconciled myself to the circumstance that the finishing of the floors will be sub-optimal, but I am open to all strategies and  I will defer to your wishes.