I don't see that it was ever mentioned that in 'normal' circumstances during bay servicing the drogue shackle bolt was only ever assembled (bolt fitted) before fitting to an open scissor shackle prior to it being closed and the BTRU cocked. If the bolt was incorrectly fastened it would be clear as the drogue shackle would not have fitted. Is it the case that the in-situ removal of the bolt was introduced to allow the crack detection on the seat beam to be carried out 'out of phase' with the seat servicing? If so I'm suprised the SI did not mention what assessment was done when it was introduced.