populating like thispopulating with query string and php

So I just did this instead of having a bunch of filters for populating and it worked. Is there something wrong with this?

add_filter("gform_pre_render_3", "pre_render_function");
function pre_render_function($form){
	$_GET['myval'] = "Augmented Reality,Cloud Networking,Carrier Class Solutions";
	return $form;
}

This way I can just query my database and set all my return variables as $GET variables in one go and it works.