I suspect some--by no means all--preceived "time wasting" is an issue of perspective. I almost always start off contact with an e-mail or PM introducing myself, telling a bit about myself, saying the range of dates I expect to be in her area, and giving my references/P411/D-C info.
A significant part of my decision process is how she responds. A no-reply will end my interest right there. A one-line form responce will likely do the same. A personalized responce will usually cause me to pursue setting up a date. Unfortunately my work schedule is not always my own and so I sometimes don't actually get there, and have to cancel (at least a day's notice, usually a few days notice).
Most ladies are understanding, but I have been scolded as a time waster for not following through after my one introductory e-mail, and for having to cancel/eschedule because my business trip didn't happen. In my world view, that is not time wasting, but some ladies do consider it such. The English language is filled with ill defined terms.