v2007: nlapiLoadRecord v slow

i'm finding nlapiLoadRecord very slow in one particular case - does anyone know if there's a good reason for this?

i have an afterSubmit script running on phonecall records and the following line is causing a delay of 20secs or more (sometimes timing out):

var callRecord = nlapiLoadRecord('phonecall',recordId);

i'm trying to do the following:
1. add a note record to a phonecall
2. edit the phonecall and clear some fields
i'm running the script after submit so that any errors in creating the note record don't stop the phonecall saving.

so i'm loading and saving the record that triggered the script - is this the cause of the delay?