After finding a 1970 reverse of 68 on the first 1970 I happened to check in pocket change a few months ago, I've been curious if this variety is actually rare at all. I don't typically hunt dimes, so I didn't have much data, but I did my first dime roll hunt today (just $50), and thought I'd share my results. I found four 1970s, of which two were reverse of 68, two 1970-Ds, of which one was reverse of 68, and two 1969s, of which one was reverse of 68. So of all three possible year/mint combinations that can show the variety, exactly half the coins found for each were RDV-002/reverse of 68. I'll leave people to conclude what they will from this very unscientific, small study, and please feel free to chime in if you're a dime hunter with your own anecdotal data!