The debate about lay-bys on the historic battlefield illustrates the good, the bad and the disappointing of the planning system.  Road-builders throughout the UK follow a 3-stage process set out in the Design Manual for Roads and Bridges (DMRB).  This is the bible which provides standards, advice notes and other documents relating to the design, assessment and operation of trunk roads.  Jacobs and Transport Scotland followed it assiduously.
From the start, the promoter had to assimilate guidance on how to deal with unavoidable impacts on the battlefield.  Thus Historic Environment Scotland (HES) was made a statutory consultee and the scheme was developed in accordance with Scottish Planning Policy and HES
Managing Change guidance.
At Stage 1 of DMRB, indicative corridor options are explored along with general strategies for key elements including lay-bys.  HES was informed about the necessity of lay-bys but was not alert to the damaging impacts of siting lay-bys on the battlefield such as how these affect the design or the footprint.    As a statutory consultee, HES’s remit was to ensure that the developer tried to protect, conserve and, where appropriate, enhance the key landscape characteristics and special qualities of sites in the
Inventory of Historic Battlefields at every stage of planning.
At Stage 2 of DMRB, the options for alignment are refined until one is chosen. The developers considered locations for lay-bys at this stage.  To comply with advice on driver safety, they knew that lay-bys would be required northbound and southbound on the battlefield.
At Stage 3 of DMRB, the chosen route went through a final iterative refining process that led to detailed plans that showed the public the location of lay-bys for the first time.
When the final plan was presented in November 2017, HES objected
inter alia to siting lay-bys within the battlefield but withdrew its objection after the plan was modified a little.  The lay-bys remained because Transport Scotland insisted that driver safety is paramount.  Simply eliminating lay-bys from Killiecrankie without building replacements elsewhere would extend the distance between successive lay-bys to 13km (8 miles) northbound and to 7.5km (4.6 miles) southbound.
The Reporter appears to sympathise with our frustration that the lay-by question was not resolved right at the start of the DMRB process.  “I can well understand why objectors would seek to have the lay-bys sited outwith the battlefield, and especially so as only 3.6km of the dualled route would run through the battlefield.  It might in fact seem perverse not to have done so.”
We still maintain that a better balance of competing interests could have been achieved with less earthworks and a smaller footprint on the battlefield had a decision been taken at Stage 1 to veto lay-bys on the battlefield.  Then Jacobs and Transport Scotland could have worked through the iterative process knowing that they had to try to space regular lay-bys every 2.5km without encroaching on the battlefield.
Alive to the possibility that Ministers might have wanted to reduce the footprint of the scheme within the battlefield even at this late stage, the Reporter suggested that they could do so by eliminating lay-bys from Killiecrankie.   However, they declined the opportunity and have accepted the plan without any major modifications.