Only one rest break required if working more than six hours, says EAT

If You are a smoker (and this is indeed an addiction varying in levels from person to person) and your employer imposes such restrictions. Then should they not also offer a solution, such as free nicotine replacement therapy in the form of patches or councilling?

Whatever the EAT has said about rest breaks doesn't alter the duty of employers under the Health and Safety (Display Screen Equipmen) Regs 1992 to ensure that DSE work is regularly interupted by breaks or changes of activity.
Enlightened employers are usually aware that ensuring breaks are taken enables the workforce to maintain consistent levels of performance. Sadly there are still some who prefer to see a sprint start followed by a step nose dive in performance from tired, disengaged workers. They're making rods for their own backs, did they but know it.

lets all pretend to be smokers - enough said!

Scary stuff and "counter productive" in terms of performance for more than 50% of DSE operators who experience Screen Fatigue (HSE RR561) and may be not only at increased risk of errors but slips and trips or other more serious mishaps for some time after prolonged periods of screen work.

Remaining seated for prolonged periods without a break also increases risk of deep vain thrombosis, as per long haul flight, let alone increased physiological (MSD's) and/or emotional stress associated with effectivley being captive....!

If the security work involves mainly CCTV monitoring then both these workers and DSE operators should be "special cases" under Reg 24 !!!