If I had lots of spare money I'd probably buy another bike - and then it would be some 6" FS type thing, stick my big and fairly knobbly tyres on that and ride it in drier conditions and put slightly less huge but more knobbly tyres on the hardtail and ride it in wetter muddier conditions. But I found myself thinking, what do I want a full-sus for? I enjoy riding a hardtail over rough stuff (rock gardens, w00t!) the local trails are relatively smooth anyway, I'd no longer have the "I'd be quicker on a full-sus" excuse and might start taking more stupid risks but a FS would make casing jumps less unpleasant. That doesn't seem a great reason to buy one!
I'd thought about having a second wheelset in the past but then realised I'm too prone to wearing out cassettes and the wet/mud wheelset would doubtless end up with a more worn cassette which seems like I'd be inviting drivetrain annoyance? So how about just having a second front wheel, so I can swap between (current preference) a Rubber Queen (huge, quite knobbly) and Baron (not as huge, more knobbly, stickier) as conditions dictate? It's all about carving the corners on steep loose trails for me at the moment and the back tends to follow as long as the front sticks.
Madness or genius?