I am new to the RW Community. It seems to be relatively inactive. Moreover, it is difficult to use. For example, the latest post is not listed at the top of the page, but rather the bottom, forcing one to page down many pages to find it. Also, I have been unsuccessful in downloading .und files posted by other members. It seems that all that I get is a file of html source code for the web page in question rather than the .und file. A new issue of "Tips and Tricks" supposedly is posted every other week, but I have yet to see any new ones posted. Any one have any tips to make this site more user friendly?
I haven't yet made the tests you indicated, but I'll take your word for what you say about the same stocks being selected. The only thing you might want to consider is whether you know for sure whether some stock that did not survive for a full 52 weeks (delisted, bankruptcy, no longer covered by RW, taken over, etc. etc. ) actually would have been been selected by the screen in question. I have no doubt screens can be devised that would be subject to survival bias because of the limitations of RW backtesting. Some screens may be more vulnerable to this than others, and it would be well to keep this limitation in mind.
In general, on a broader issue, I'm not sure how stocks that are no longer listed are handled by RW in backtesting. For example ABD and FO are stocks that are no longer listed, but if you build a screen selecting these stocks by ticker, neither are ever selected when backtesting, even during periods when they were extant. Conversely, a newly listed stock, ABBV, is picked up by 1-week backtesting after it became listed after 1/1/13 even though it does not even yet have a 52 week history.