It is quite difficult to get the tip just right. Take my Endura for example, the method for sharpening the serrations always leaves the tip 1cm or so of plain edge blunt or uneaven. My only recourse was to use one of the Pro-Files and hone it by hand, equaly the triangle white stone free hand works almost as well. However this never 'quite' gave me the perfect 20 degree angle. This is what I now do...
Once the serrated part of the knife is perfect, I choke up on the front of the knife (BE V E R Y careful

) I use my finger as a guide on the last serration peak near the plain edge (place finger on the flat side of the edge assuming you keep the chisel grind, it aught to be safe if you are careful). I then make sure the tip and only the plain edge tip area goes straight down thw white flat step 4 stone. You have to be VERY careful not to round off the tip. The way to avoid this is to ensure the angle stays the same when you finish the downwards stroke and the tip passes over the stone in an even manner.
Here is a 'tip'

do it slowly, I am talking about 2cm a second at most!

. I do this three or four times and then once on the other side once I feel a 'burr' form. Make sure you examine for a 'burr' each time and be light and slow. Looking at the plain edge under the lightbulb shows once the edge is sharp and it is a simple matter to feel the 'burr' form on the other side. You want to go slow for obvious reasons but mainly because if the flat step four is allowed to run across those 'perfect' serrations you will have to go back and finish them again

! I tried doing the tip first, but doing the serrations ruins the work, so I advise you do it last.
The best way to think of it is if you had a 1-2cm plain edge blade to sharpen and every other part of the knife is the handle. I even tried wrapping the edge in a cloth to protect my fingers, but it made it harder to control, you could tape it up and it would be done in a couple of mins rather than 10 or so my way. However I dislike taping a knife blade up as the sticky resedue is a pain to remove and the time spent putting it on and taking it off work out about the same. However I suppose it would make doing the job more simple and certainly be safer!

. Saftey not being a high priority for me

!
Let me know if it helps or if you have any other questions.
Peace