Felt roof - To Lap Or Not To Lap?

[walkingman]

Just laid the underlay of my flat roof two layer self adhesive felt system. I'm using Wickes easy seal as I've read some good reviews and so far its been a breeze.
Folly or not I have opted not to use drip battens on the three sides of my roof where there is a check kerb present. Therefore, my question relates to the usual method of laying the cap sheet.
My roof is 5.3 metres wide. What would be a reason not to run a single 6 metre capsheet across the roof over the kerbs and down both sides. folded under and tacked down at the edges? I have some underlay left over so I plan to lap that over the kerbs as well meeting the folded under capsheet on the fascia.
This avoids the use of kerb edge laps and a join in the capsheet. That can only be a good thing right?
Obviously at the gutter edge and possibly at the top edge I'm going to need laps (although I'm furiously trying to work out how to avoid it on the latter).

 

[cotswoldbuilders]

As a diy job and not the proper way, you could do it.

The drips and kerb trim are different, the drip trims need doing prior to cap sheet.
Kerb trims last, they are tacked to the outer side of kerb, then folded back over the cap sheet.

 

[walkingman]

Hi cotswoldbuilders
I plan on going for it tomorrow. I'm guessing from your reply that there are no disadvantages to doing it my way?
One thing I have thought of is that I will need to apply mastic to the top of the gutter laps before laying the first strip or at least before I fix it over the sides as I won't be able to lift it near the edges afterwards. I am so relieved I thought of that now!
You say it's not the proper way, which it clearly isn't as I can't find any reference to any other method but the 'proper way', despite extensive searching. But why is it the proper way to create a join in the cap sheet where it could be avoided?