Jcleppe, Sorry, didn't get a chance to finish editing my last post before you and Pima replied so please check it out.
Pima, It really isn't impossible to do crunches with the correct form and average less than a second per. Super fit dose NOT equal fast situps/crunches. I've seen ppl who are very fast runners and can do many pushups struggle badly when it came time to do situps/crunches(Trying to be politically correct by using both until someone corrects me. Im so confused, don't know what to call them anymore. How can it vary so much between branches? We're a marine family so this is new to me). I have also seen and heard of a few others who can do a situp/crunch in less than a minute. I'm not the fastest runner, neither am I a beast with pushups, but after doing situps/crunches almost every day since at least middle school and beyond, it is where I am the strongest.