I used to dry bullnose, riser and steps by using vacuum hose cuff also but because I'm in pretty great mood all the time, I go back to van and get my nozzle ( similar like car wash places have) , but blue one. Since my last cuff is swivel, I just push it in the cuff and swivel it away. It does a great job and the stairs look all groomed. When drying bullnose, all you have to to, is cover half of the vacuum slot with your index finger and it's all good...I have had one callback this past year and it was a good learning experience. It was a set of white steps that I cleaned. On the bottom three steps, there was an off white discoloration on the bullnose. Ive cleaned this house many times and it never happened.
These particular steps had carpet in the middle and hardwood on each side. What occured was that after the cleaning, I vacuum the bullnose with the hose cuff. Since the bottom steps were unusually soiled, I did have some overspray on the wood and I vacuumed the wood first thereby introducing soil in the cuff. Then I proceeded to vacuum the bullnose. And then up one step and do the same.
So now when I have overspray, I vacuum the bullnose first to the top of the steps and then the wood going back down.