1) Its needs quite a lot of prep which is something that is commonly forgotten (or should i claim ignored) around here.What are those reasons exactly?
2) Reveals the users position, leaving Jiraiya even more vulnerable w/o Ma and Pa's help. Not that their presence would make any difference because none of them can keep up, hurt or keep the the 3rd way.
3) Jiraiya also had a plan which worked on the Paths', but the Raikage is different. He doesn't care about Katon and much less Doton, making it impossible to make time for Ma and Pa.
4) Assuming he could pull it off. He still can't hurt the Raikage. What's your point?