Hi Serenus, welcome to the forum.
Yes, re-writing good advertising / sales copy can help. But as Franklin indicated, it’s not a complete training program all by itself.
The idea has been around for many years. If my memory serves me correctly, I think I first did this exercise when I took the Randy Gage copywriting course (maybe 10 or 12 years ago) although I didn’t copy out 100 pieces, it was more like 2 or 3 long form sales pages.
And when I went through the AWAI accelerated copy course (around the same time) they had me write out a couple full page control pieces, multiple times.
The benefit to this exercise is it can help you get a first hand feel for writing a good piece of sales copy. And it can possibly help you understand the structure and flow of a good sales piece through some sort of physical, or psychological, osmosis?
But that’s about where the benefit ends.
You still need an understanding of consumer behavior and buying motivations for any particular market, if you want to have the best chance of your copy getting a high response rate.
The other downside to it is the boredom and fatigue, not to mention the hand cramps from writing 100 pieces of copy by hand. But as long as you’re dedicated to completing the task then it doesn’t hurt to do everything you can to advance your skills.
As far as where to find winning copy that you can write out by hand, check out
Swipe-Worthy
The owner of the site, Mike, has a huge amount of swipe files for you to choose from. Just look for the ones marked “control” – Those are the ones that were the best performers.