It really depends on your reason for pruning, and the individual plant. If you need to prune, the general rule of thumb as Tiffany mentioned is to prune immediately after flowering. The reason for that is that some shrubs flower on old wood from the previous year (and some on new wood and some on both). So if you prune in spring before flowering you will lose the flowers that formed in the previous year on the first type and it won't bloom at all that year if you prune all the branches. That particularly applies if you'd be shortening all branches, say for something that has dead flowers or fruits at the end of most branches still in spring.
The method suggested on your link (to remove a third of the branches to the base every year) is standard advice for keeping a shrub from getting too big. The two thirds old wood remaining on the forsythia would still flower and it certainly is easier to see what you're doing for that kind of pruning when there are no leaves - forsythia starts to leaf out before the flowers have fallen.
There are some plants on your list that don't usually need anything other than dead stuff removed, and at least one won't regrow from old wood (Genista lydia) if you cut too far back, as far as I recall. I'd suggest looking up pruning recommendations for each plant individually, or get a good pruning book that lists the different plants and how to prune them. For some plants the timing and method vary even within the genus, for example clematis.
As a general rule it's best not to prune in fall (more chance of fungal diseases gaining entry and causing die-back).
What I do with Russian sage is cut it back to a few nodes above the ground as soon as I see signs of buds swelling. Several of the others I don't usually prune other than dead or diseased wood (have no space limitations).
We could maybe be of more help if we knew the reason for pruning each plant.
