Jd, in reality, they should, but if the angle is not that much greater there is no reall issue, but..you will lose some of the tension force , in full in main sheet.
What happens when the angle is greater, is that after you sheet in as much as possible, the sheet no longer tries to pull the boom downd, but starts pulling it backwards.
The King 40, by Summit, has the arrangment you are seeking for and they are ok with it. Its 95 degrees or so.
If you are desperate. you can do it..and the only reason is because you have a traveler. How big is the one you want to instal? Because if the traveler is big, by moving the car you can compensate for that, but yo will lose a little of the characteristics of the system. Use only Dyneema if you do that
MAke sure the gooseneck can take the pulling effect.
See this site and serach in the galleries, you can see the King 40 and the 100 degree sheet..they made the boom 2 feet longer than the sail for that
The King 40 | Summit Yachts