Those who use writer's block as an excuse for not having written, well they need to either stop calling themself a writer or do something about the blockage.
There is no one size fits all solution to dealing with writer's block. For some, bashing on through works, others need a different approach. To determine what approach is going to work, one has to figure out what is causing the blockage.
There are a lot of things that can cause writer's block: physical illness, mental illness, extra stress, traumatic experiences, the perfectionist monster, the worthless piece of scum monster, the lack of discipline monster. the procrastination faerie. (Yes, procrastination is a faerie instead of a monster because it lures you into playing just one more game of minesweeper, posting one more thing on a forum, etc.)
Once one has figured out what is causing the blockage, one can choose the sword to use to defeat it. The bash on through sword doesn't work very well against the perfection monster. The perfection monster sneers at the writer's puny efforts and points out all the flaws in the work that is being bashed out. It's probably more effective to either tell the perfection monster to shut up and go stand in the corner or send him out for a beer. Another powerful sword to use against the perfection monster is the "permission to write absolute crap". I use that one myself quite a lot.
There's no magic cure all for writer's block, but determining the cause of the block will lead one to the appropriate sword to smash it.
** Shamelessly borrowed from Heather who coined this phrase.