The risk with saying "Yes, if.." is that a lot of managers (or clients or whatever) stop listening after the word "Yes".
With "No, unless ...", it's a different story. Then success is dependant on the conditions mentioned and they're much more likely to do their part in making sure those conditions are met. If you said "Yes, if" they'll often just remember you promised you could do it and leave it at that.
With "No, unless ...", it's a different story. Then success is dependant on the conditions mentioned and they're much more likely to do their part in making sure those conditions are met. If you said "Yes, if" they'll often just remember you promised you could do it and leave it at that.