I wouldn't be overly concerned about idling. Most people who have issues, especially with exhaust regen, are simply babying these things. I used to use the high idle often during cold months, and never hesitated to get into the turbo when pulling. Never had to do the exhaust regen. I used to work with a guy who his truck did it quite often, because he drove it to and from work and that was it. These things are pullers and designed to work.
My understanding is they will regen at a set mileage interval regardless of what the DPF fill is. They will also regen when the DPF is "full". Its when they can't complete regens that they have to be manually initiated by the dealer/shop to complete a cleaning or removed and cleaned.
