In Reply To:
I think you're comparing two different things but it could be useful.
If your 30 min TT time is slower than your 500 y would predict it to be, you need to work on threshold
If your 500y time is slower than your 30 min TT predicts it to be, you need to work on vo2 max
At the pointy end of the field, you're probably right. For myself, I think my technique is still lacking a lot. The shorter the distance, the better I do, but I think it's just dumb muscle. Over a longer distance, even 500m, I can't keep it going and settle into a much slower pace after the first bit. Of course, I haven't been doing the work for decent swim endurance lately either but I think poor technique still plays a bigger factor in the longer TT. Or am I not thinking about this the right way?