As I recall, the Silver Palm ran down the interior of North and North-Central Florida on the CSX "S" Line, past Gainesville, through Ocala, Wildwood, and Lakeland, to Tampa, then back through Lakeland, Then it joined the rest of the route that 91/92/97 98 covered down through Winter Haven and on down to Miami. The Silver Star and Silver Meteor did not service those stations. The Palm had a contract to carry U.S. Mail to those interior cities, and when Amtrak elected not to renew the contract to handle that mail, I think that's when they truncated the Silver Palm.
That created a problem. They apparently didn't realize the magnitude of the ire generated by the loss of rail service to the Tampa area. They bustituted the rest of the "S-Line" stations without too much of a problem, apparently, or that business just went away. But the Tampa station generates a LOT of revenue. Every time I've been there it's been REALLY busy.
So what to do? Re-route 91/92, adding a dog-leg between Kissimmee and Winter Haven through Lakeland to Tampa, then back through Lakeland again! And that seems to work. An interesting but strange result to this (and I do NOT understand the reasoning behind it) is that you CANNOT book travel on Amtrak between the Lakeland and Tampa stations on 91/92. Maybe they couldn't figure out how to keep track of which time each train was going through the station, since both 91 and 92 stop at Lakeland TWICE each day. But it still seems rather silly to have a blanket prohibition on that revenue just because they don't want to try to keep track of it. Go figure.
One nice thing from my personal standpoint is that it gives Orlando residents a really nice day trip by Amtrak to Tampa - 91 gets us into Tampa before 1 PM (depending on how late it is) and then 92 departs Tampa heading back towards Orlando at 5:27 PM. That gives more than enough time for a leisurely stroll several blocks to get on the TECO Trolley (more rail!!) over to Ybor City, another 5 or 6 block walk to the historic Columbia restaurant for a really nice and affordable lunch, take the Trolley back to the Tampa River Walk, or the Florida Aquarium (etc...), then back to Tampa Union Station and back to Orlando.