I would love to know where you found this method? I have read a lot of herbalism books and went to school for Chemistry and nothing I have seen would suggest this. In fact my organic chemistry knowledge is screaming that making things colder make everything run slower. By freezing something you may be rupturing the cell walls but the ice crystals are shredding and denaturing all of the compounds you are extracting. As a general rule things move fast at higher temperatures since the average speed of the molecules increase which has more energy to react. If you wanted to get this done faster you would need to heat the solution not freeze it. Especially since OP is using the standard Folk Tincturing Method method which works great if not fast. I have seen modifications that start with the solution below boiling and then let sit for time but that is generally done with things like honey which is easier to pour that way. I haven't seen it with alcohol since that will reduce the alcohol content since the alcohol will boil before the water.

I know when making a cocktail you want to put the herbs in the cocktail shaker first and then muddle in some liquor. This will allow the cell walls to rupture and the alcohol will pull out all of the flavor. After you add ice and shake with the rest of the ingredients. The solid ice will continue to break the material and the additional water will extract additional materials while chilling down the drink which provides a better flavor. But you don't freeze it.