thief shortbow geting invaled target

i have been doing some thief tests in wvw and i have found that when i use sb5 i sometimes( this is most times) will get the invaled target. i have also found that this is becouse of the arce of the bows shot and it sometimes make the target up or below the location i target. i think inorder to fix this you will need to do more codeing on the shortbow 5 skill so it more reliable. as far as i can tell this is the issue for invaled targeting for sb5.