Hi Bo,
In fact, there are times when playing double tongued is worse than single.
The double staccato is done preferably in quick passages. When these passages involve notes grouped in three or six, the best is to do the triple staccato, that is "pronounced" as TKT TKT...
Thanks, that's what I thought too...
My source of confusion was that in many staccato exercises I have found recently the instructions are to play them double-tongued... They must all be in groups of two or multiples of two.