Chimbu,
So, where in the world is to/two six thousand an altitude?
Fair point mate,
obviously not much room for misinterpretation here, but consider the use of the word "to" when descending. Believe it or not, it has happened before where the word "to" has caused some confusion as to the cleared altitude. In one instance, for the unfortunate crew of an unfortunate 747, culminated in controlled flight into terrain.
"...ATC radioed to the flight, "Tiger 66, descend two four zero zero [2,400 ft]. Cleared for NDB approach runway three three." The captain of Tiger 66, who heard "descend to four zero zero" replied with, "Okay, four zero zero" (meaning 400 ft above sea level, which was 2,000 ft too low). The proper radio call from ATC, instead of "descend two four zero zero", should have been "descend and maintain two thousand four hundred feet". The captain read back "okay, four zero zero" where the proper read back should have been "Roger, descend and maintain four-hundred feet"...."
source:
Flying Tiger Line Flight 66 - Wikipedia, the free encyclopedia
Clearly this is an example of a prized f&*k-up, but if there is ambiguity to be had out of a phrase then a "standard phraseology" shall be employed, don't you agree?
I say "do away" with use of the word "to".