I don't think it is so much a matter of the actual method used to dose, but rather the total amount and how quickly it is added. I drip because it is easy and IMO reasonably safe...but there are other methods. Key being, don't add too much too quickly.
On the solids...I use Mrs Wages, which is less "pure" than most commercial mixes. The outlet to my doser is mounted about 1/2 inch or so above the bottom of the container. I always let the kalk settle for at least 4 hours, usually longer, before dripping. The kalk contains metals and other undesireables...you can see all kinds of little black specks in the leftover mix at the bottom...don't want that stuff in my tank...
I'd say pouring an unsettled kalk slurry into the tank is not a very good idea...
MikeS