You could always do it properly. Decant off into another bucket/FV containing the priming sugar dissolved in water. As the beer goes in it creates a mixing circulation which distribute the priming sugar evenly throughout the beer.
Uh, that's precisely what I did, and what I always did. For some reason the mixing circulation didn't really work this time.
Firstly, did you syphon from your Seconday into you bottling bucket?
Yep
and assuming the syphon tube was as the bottle of the bucked did you? :
interesting assumption
Add the syrup to the bottom of the bucket totally?
Yes
Add half of the solution at the bottom, and the other half, around halfway through transfer?
or
Transfer all the beer to the bottling bucket, then pour the syrup in?
I like the half and half idea... I also think adding the syrup afterwards would be likely to lead to syrup all just falling to the bottom of the bucket
Also, what did you use to make the syrup up? I tend to use about 300ml boiling water with 70g Ivert sugar, and then cooled to below 30 degrees before adding to the bottom of the bucket.
I used about 120g sugar in about 1/3 of a pint, boiled. This amount tends to work OK for me. I also hardly ever bother letting it cool that much -- maybe to 60' or so. As it's a small amount, being added to many litres of beer I can't see that it makes much difference.