I've used plastic covers to warm up my beds faster in the spring after a wet and cold winter, but not to germinate weeds.
I think its better to let the weeds be. If they are deep underground and you don't double dig or till, then they stay there dormant if not disturbed.
Just add 2-3" of fresh compost to the top of your beds and transplant or sow your crops. Don't dig around and bring up the weeds at all.
If you must add amendments or fertilizer, again broadcast over the tops of your beds and rake it in just lightly. Don't ever go deep.
In raised beds you don't compact the soil so you don't have to dig it up to plant anything. Its naturally friable.
Anyway, that's what works for me.