Interesting. Here in Asia "black top" roads are paved with a hot mix, usually laid in 1 - 2 inch lifts, and compacted with the "finish" compaction done with steel rollers which are usually flushed with water. No sealing, as you describe is used.
I wonder whether it is the difference in tempratures that makes the difference. Over here road surface temperatures can probably exceed 40 degrees C and, in places like Northern Thailand, perhaps be as low as
10 degrees C in the cold season. Bruce in Bangkok (brucepaigeatgmaildotcom)