I recently sowed 20 seeds of Sunflower Teddy Bear in compost and only 3 germinated. I tried the other 20 in damp tissue and 17 out of 20 germinated. Its quite an interesting method to use for testing seed germination.
I had poor results with T & M Spinach Medania with only 6% gemination in seed compost. Tried again in tissue and achieved 10% germination so I was confident in complaining to T & M . Clearly a poor batch of seed.