You scared me for a second- when I saw that statement, I thought you might be right, but senescence is a biological term with it's root being something similar to "senile". The statement probably means that the flowers will last longer without dying of old age, not that they will fail to mature. This would make sense as silicon is known to strengthen the cells and protect them from damage. Although only a few runs, I used silicon from start to finish. I had better than average results, with room for improvement, none of which had anything to do with delayed flowering, but just normal learning curve stuff. I am fairly certain that Homebrewer uses it the full grow, but I don't wanna answer for him. If you are feeding to much nitrogen, it can delay flowering. Also, if you expose them to any light during the dark cycle- even just a minute or so, or perhaps a nightlight/status light in the room, it can reset the flowering stage I've read. Any of this seem applicable?