I think you a right Peter. Unfortunately i just used it to try and get the last few moving down from the branch and into the hive a bit quicker. i only used a few puffs of smoke and unfortunately trying to like the smoker easily i grabbed some cardboard and put it in.
i definitely will take that out into account for next one. i think i will give it a shake and let the rest walk in. It was a good lesson learnt. im glad i didnt use that bit of cardboard in my smoker on my good hives. from now on straw and hessian is my only fuel.
It was definitely not heat related as it was done at 6pm and then the rains came so didnt get over 25deg and lots of ventilation. such a shame.