For mechanical estimators
Mechanical layouts bury their symbols in ductwork and pipework linework. EasyTakeoff matches each scheduled symbol's own geometry, so distribution routing stays background and the count stays clean.
Where counts go wrong
A damper symbol sits ON the duct; they overlap completely. EasyTakeoff counts the damper as a damper where pixel tools see one merged blob.
Square diffusers, grilles and access panels are all rectangles with internals. Each location counts toward the one class actually drawn there, with no double counting between neighbours in the legend.
Older mechanical packages mix CAD sheets with scanned record drawings. EasyTakeoff detects each kind and handles both. You review with the same queue either way.
Mechanical layouts revise constantly. Counting is deterministic and fast, so re-running revision C is minutes, and the diff between your two exports is your change schedule.
In practice
Upload the ventilation and pipework layouts, keep each system's sheets grouped in the project, and let the legend define the classes. The engine counts, you clear the review queue, and the export gives you per-sheet quantities ready for the schedule of rates.