Mystery of implant apical radiolucency

Just placed a couple of BLT and once again my immediate post-op and have my lovely apical radiolucency. I’m clearly a master clinician. Finally I may have worked out the reason for this. I’m using straumann velodrills and placing BLT implants, as previously advised by the straumann team this is not an issue. Due to morphology of the drills vs the morphology of the implants this may be the reason for the radiolucency ? Does anyone concur, have I cracked it ?