And this is his answer to Rasmussen's question on what Worf considers an important example of progress. So essentially Worf should be saying "Phasers were invented in the 22nd century - first there were none, and then there were some, which is important progress in my opinion". He just chooses brevity in saying so.According to Worf, there were no phasers in the 22nd Century, and he would know.
Rasmussen wants "progress in the past two centuries". So Worf would mention the 22nd century no matter whether it was an important watershed in phaser tech or not. But the way he says it, and more importantly the reason he says it, allows for the watershed to have been in that very century.
Timo Saloniemi