Diagonal bracing on pitch roof

[^woody^]

if the roof starts to spread that the rafter will pivot at its top edge which will then try to drop

I'm not following that. Firstly there is no pivot. There can't be with any type of rafter movement unless the bottom end moves upwards.

Secondly, the roof can't start to spread and cause the top edge to drop. It is the ridge beam that must fail before any spread can even occur.

Fixing is simple. A seated rafter, a gusset, or just spikes. The load is only vertical and perpendicular to the rafter, and the rafter is not trying to move outwards.

 

[Faceache]

Thank you to everyone who responded, it's much appreciated.
I think it was princeofdarkness who mentioned nailing metal banding over the pairs of rafters where they meet the glulam at the top, which has been done, but I neglected to mention in the original post.
Even though I have birdsmouthed the rafters over the plate I was told to use the glide shoes in addition to this so that is what I have done.
Inspector calls on Friday so hopefully what has been done is correct and I can get on with nailing 8000 odd 11 x 7's into place. Can't wait.
Thanks again one and all.