Tip: Layer 3 backgrounds and tides disappear when you hit a message box, so plan your level around that. For example, you can add a sublevel without layer 3 at the start/midpoint, and include your message there.
This patch changes the behavior of the springboard sprite in two ways. The first prevents Mario from being able to regrab a springboard very briefly after it's been kicked. The second prevents Mario from losing his x speed on the same frame a springboard is picked up.
A simple but useful patch that smooths out the springboard's behavior some - this patch could make all the difference in an intense platforming section based on springboard setups.
Note that, after applying either fix, turning it off and reapplying the patch will not remove the applied fix. Note also that it is still possible to have the springboard clear the player's Y speed if contacted in a particular way due to an unrelated routine.
Tested with Asar 1.71, Lunar Magic 3.10, SA-1 1.32, Snes9x 1.59.2.