There is a מחלוקת  between ר"מ ורבנן whether you can make a תנאי, ע"מ שאין לרבו רשות.

Why would this תנאי  not work, what is different about this תנאי  than every other תנאי?

What is the 'יסוד המחל between ר"מ ורבנן?

Could it be that they have 2 completely different understandings of the mechanics of כל מה שקנה עבד קנה רבו?

Enjoy!!  8 minutes