Although Steve Whitmire started performing Ernie in 1993, it seems like they were REALLY trying to give Kermit a Sesame Street comeback in 1996 or 1997. Of course it seems Whitmire might have had a limited Sesame Street schedule at first (and he's rarely been any other characters on Sesame Street) and then started to perform Ernie a lot more regularly around 1998 until about 2004 or 2005 before being less involved on the show. And yet most of his performances as Kermit were in the very late 1990s, with him appearing in a few Sesame Street specials during those years, as well as being in two of the "Slimey goes to the moon" episodes, making a brief cameo (I don't think he even had dialogue) in a season 31 episode, appearing in a few group publicity photos around that time (which wouldn't actually require Steve Whitmire, but it was rare for him to be in Sesame Street group photos even during Jim Henson's time), and getting his own home video compilation. Not to mention that the light and dark sketch with Grover was most likely from the late-1990s (I don't know for sure what season it originated in, I can only go by the earliest known appearance to Muppet Wiki, which was a season 29 episode). And yet despite it seeming like they may have been giving Kermit some kind of SST comeback (at least in terms of new appearances), it seems like they started showing his old segments a lot less often at that time. I watched season 30 almost every day during that seasons run (more than I had previous seasons, though I did catch a fair bit of season 29) and it seems like old Kermit segments were scarcely shown that year. And this was two years before Henson sold the Sesame Street Muppets.