It's only a waste in terms of the squad balance. If you look at the 4-2-3-1 formation we pretty much have 2 players for each position, the only imbalance is we have 3 strikers for 1 position and only 3 centre backs for 2 positions but this isn't a huge problem as Kenyon can cover at CB if needed.
Going to a 3-5-2 suddenly means we only have 3 centre backs for 3 positions and you then have to re-classify Kev, Oates, Thommo as strikers and Mandeville as a central midfielder as we have no use for wingers. This means you then have Oliver, Oswell, Leitch-Smith, Kev, Oates and Thommo competing for 2 spots up front whilst we have a severe lack of centre backs.
If Jim abandons 4-2-3-1 after just 2 games it's a huge admittance from Jim that not only has he got his tactics completely wrong that his whole recruitment over the Summer has been flawed. Had we gone into the season planning to play 3-5-2 we'd probably have signed 2 less forward players and more centre backs instead.
This is why I think Jim will continue to play 4-2-3-1, not doing so would be admitting he got things wrong in the Summer.