Specialist work is where density and capability stop agreeing, and one of them has to give.
Why it matters
General service can be clustered freely because almost anyone can do it. Specialist work cannot. If three termite jobs land in three corners of the territory on the same day and one person holds the certification, that person drives all day and treats for ninety minutes. The utilisation of your most expensive, hardest-to-replace technician is the lowest in the business.
How you notice it slipping
Specialists have the highest drive time and the lowest stop count. Specialist jobs are scheduled on request date rather than grouped. Growth in a specialist line is celebrated in sales and quietly dreaded in dispatch.
What to do
The second move is to widen the pool. A certification that only one person holds is a scheduling constraint disguised as a training decision, and the cost of leaving it there grows with the line it serves.
Give specialist work its own rhythm instead of mixing it into general days: a specialist day per area, or a half-day block, so the jobs cluster the way everything else does. Then watch the ratio of travel to treatment for those technicians. It is usually the clearest argument for training a second person.