Jones inherited a team that went 22-27 (0.449) over the previous 4 years and a roster that had only 3 players who would be drafted by the NFL. Jones went 30-21 (0.588) in his first 4 years - a 31% improvement...of course starting at the bottom makes it easier to show improvement but also makes it much more difficult to be elite...that takes time
For comparison, Majors inherited a team that went 28-17-2 (0.622) over the previous 4 years and a roster that had 10 players who would be drafted by the NFL. Funny, Johnny managed to do even worse than Battle: he went 21-23-1 (0.477)...that's a change in winning percentage of -23%!
But Johnny, with the help of good assistant coaches did build the talent level and the program. He had back to back SEC titles in 1989 and 1990...but he was asked to leave in 1992...
Fulmer inherited a team that went 38-9-2 (0.809) over the previous 4 years and as noted, won 2 SEC championships...the roster he inherited had 22 players who would be drafted by the NFL. Phil's record over his first 4 years was 39-9...basically he kept the Vols at the same level as Majors...the change in winning percentage was less than 1%...
What about Jones' contemporaries? Everyone loves Jim McElwain. The team he inherited went 28-21 (0.571) over the previous 4 seasons - about what Jones has done. But in terms of inherited talent, McElwain was a lottery winner. He took over a roster with 7 players drafted after his first year and at least 5 are projected to be drafted this year and as many as 9 could get signed...he inherited talent similar to what Fulmer did