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I am a huge fan of rotating your gear. Don't wear out your gear until it's on its last leg. Get new stuff while your current stuff is still in OK shape and that becomes your rain gear (specifically, helmet-gloves-boots).
I am actually getting a new suit this year, so my "old" leathers will become my rain leathers. I may still run rain gear over this stuff, but only if it's real wet out.
As for rain tires, they are great but I only recommend them to riders planning to do a lot of trackdays. The frequent trackday rider will encounter wet trackdays - why sit around when you can be having a blast on rain tires.
For the infrequent trackday rider, you should be on street tires anyway (like the Rosso Corsas, which are street tires - the Diablo Supercorsa is the race tire). A good street tire will provide about 75% of the traction in the wet.
That means your lean angle, braking and acceleration need to come down a bit - but you should still be learning by enountering the conditional limit.
In other words, the limit in the dry and wet is different to the bike - but there really is no difference to the rider. The feelings through the bars,seat,pegs are similar.
The same skills and process you use to ride at the dry limit are used to ride at the wet limit. People crash in the wet when they try to apply a DRY limit to a WET surface.