Making progress in a mainstream fighting art (or martial art) is quite
fast compared to the internal arts.
How come?
The external arts require the student to adhere to the katas, techniques and
skills of the respective art.
Nobody is expected to be relaxed throughout, or to pay attention to internal
body usage principles.
Being aggressive and tense is acceptable.
A person can make rapid progress in a mainstream art because to some extent they
can use what they already have.