very different scenarios iirc
at spurs he was still getting results, albeit with not many goals scored and a style of play some fans didn't like, there were also some shocking hammerings, but we were still on course to get roughly the same points tally as before and 4th was a possibility, I think levy is pragmatic enough that he'd take CL qualification over pretty football, the sacking was due to personal relationship breakdowns
at Chelsea, RA hired him to rip the squad up, break the cliques and build a new team, RA then sacked him because he was trying to rip the squad up and break the cliques whilst building a new team
also I think in certain situations he dealt with the pressure ok, in the two highest profile ones he had a go at the fans and a go at the press, but in both cases he was absolutely right to do so