I wouldn't place much emphasis on Gareth being in the skate off last week. Many of the public will have assumed he was good, therefore safe, forgetting that there was no judges marks to bolster him. Being in the skate-off will inspire people to vote for him that may have been blase.
Shayne will have an existing fan-base vote, but unless he makes more progress, that will wane as the better skaters gain new fans. He was damned with feint praise, and he's not going to be able to rely on taking his shirt off every week. He's plainly better than Pasquale, but potentially more dull.