grass in the cracks

In the category of jobs that make you wonder about the uselessness of some jobs, comes weeding in the cracks of the sidewalk or interlock.

Firstly, I knew that interlock inevitably has grass or veg in the cracks. Its a law, I'm sure. I wanted to asphalt the front walk right up to the front door.  apparently, this solution is not suitable for our house... my house ,yes.... our house ,no.

I almost got away w/ poured concrete, which would be stencilled or patterned... nope... interlock.

Methods for crack grass removal: 
1. Blow torch - I have a propane powered flame thrower that you use to lightly touch the intended target and the veg dies.
2. Vinegar and salt - sprayed on the veg
3. various mechanical devices that scrape in between the bricks or cement and mutilate the veg.
We used to use Round - Up and Killex but das is verboten in Ont.
Which method is best, none. My philosophy is to go at the job in stages.. blow torch first, this is not successful but satisfying somehow.
The blade approach does the job but is time consuming.
Vinegar and salt... sure but I'm switching to Kraft Balsamic dressing... so when I eat the dandelions , they come pre- flavoured.

Weather is neat  sun and cool breezes w/ humidity coming soon.

Fix the BBQ is next  - my free replacement burner ensemble. I'll need screws or bolts that were supposed to come w/ the burner but didn't.