Showing algorithm?

I've been gone since the previous showing bug, and since it's been fixed, I can't figure out what shows well. 

thanks in advance ;u;

Show when a horse is at the top of it's grade, and that's pretty much it.  I've had horses that were 1-2 points from the next grade show for a day, and take 1st-3rd on 9/10 shows for a +15 stat gain.  This is where lower ns have the advantage, as they have more points towards what counts.

As long as you have non-specialty stats no higher than foundation level it's fine. The higher the ns stats are the harder it's going to be for your horse to win show, but depending on how high the ns stats are they can still manage to win if you show when they get closer to reaching the next grade (Listed here)
The biggest difficulty lately has been having enough horses per show to actually win stats. If you have enough horses to ensure there's 5 entries per show it's not so bad, but your horses are showing against themselves so some end up falling behind.