Ha, true. Initially I was just wondering about other peoples thoughts, but the responses got me thinking so I figured they'd be more useful if people knew more of the problem I was working on.
I agree on what you say about ground effect though, after reading more into it. To be honest I'd heard about it, but never really investigated.
I understand, but how would you calculate that time though? Would it take into account things like tire deformation, landing gear stroke etc? As only minor differences in that time would give rather large differences for the resultant force produced.