Flying Crane
Sr. Grandmaster
Well again, there are different types of sparring, as well as partner work with striking that might not be classified as sparring, so certainly there can be that interactive training experience without it being simply sloppy freesparring.I teach an art where striking is not the primary weapon, and I wouldn't want my students to go 6 months without sparring. I think that's definitely too long to spend NOT working with a partner on strikes. We start partner striking about 2-1 weeks in (again, striking isn't our primary weapon, otherwise, this would probably be the 2nd class), with a basic strikes/blocks drill that gets them used to facing a punch. That's part of the progression to sparring. They should be able to do light, controlled (there's that word again) sparring within a month of that (sooner, for a striking art).
I don't think it's fair to the student to assume they will be around for 5 years. Many things can change their plans, and if the purpose of the training is for them to be able to use it against a person (whether for self-defense or competition, or both), they should start building that ability early.
As far as expecting a student to be around for five years, well I say yes and no. When a person enrolls in a college bachelors degree program, it is expected to take at least four years. If life circumstances interfere with that process and take you elsewhere before you finish, then you don't get a degree. That's life, fair or not.
It's something of an apples-to-oranges comparison, I know, but there is some legitimate comparison there.
I am of the opinion however, that even if you train for one or two or three years, you should still take away something useful that you have learned. If you did not train long enough to get into certain aspects of training, well that doesn't really matter. You have learned what you have learned, and you can and should take ownership of that, take it with you even after you walk out of that dojo for the last time.
In contrast, if you don't finish your degree, you typically don't any credit for it in the workforce. If a job requires a BS in physics, you won't get the job if all you can say on your resume is that you had two semesters of physics at the local university, and then dropped out before completing your degree.