Correct, it would not be fair to do it to Jones, Schneider or anyone who did not have a one-way contract.
Again, it's not a huge saving, as of last year for example they had Pajuniemi on their NHL roster for one day, and 199 on the AHL roster, and were charged against the NHL cap $4,419. His cap hit in total would have been 883,750 if he were in the NHL for all the 200 days
So I'd guess for each day a contract at 750K equates to around $3,700 daily cap hit (total cap hit divided by 200 days) and they'd probably only paper transaction him on spans where they do not play for at least 1 day between games. So it's kind of a negligible difference, somewhere less than 100k-300k total in my estimation and that would be if they did that for the whole year. That amount would have to be prorated down to just until the deadline, assuming the point of doing this were to accrue cap space for the deadline.
TL;DR, I am not going to try to figure it all out, yet it could save them a little bit of cap space for the deadline.