David - Machinist in wood
That's exactly the way I used my 733 for 20 years until the motor finally gave up the ghost in 2016. Matter of fact, there were plenty of times when I didn't even use the lock and the result was just fine. It is definitely better to lock the head, though, on final passes.I have a suspicion that you are locking the head down each pass while you are bringing the board down to final thickness.???
I've found that to be unnecessary and a PITA. Not locking the head will indeed introduce snipe---but when you come down to within about a 1/16" to 1/32" of the final dimension and then start locking the head it will give you enough "meat" to plane out the snipe. Assuming you're not into sanding it out.
As for wear & tear on the locking mechanism ---- I've had mine for about 20+ years (?) and it still functions like new. So i think your concerns are not really well founded.