To be fair they had little choice but to go with Shares. They had a contract with both companies, could only go with one. They coul get rid of the Sabre contract through US Airways bankruptcy but couldn't get rid of Shares contract because HP wasn't in bankruptcy. So choice was to continue to use both systems until one of the contracts expired (Sabre's contract expired before Shares) or switch to Sabre and continue to pay Shares for the duration of the contract or pay a huge penalty to Shares to get out of the contract. So, it isn't hard to figure out what to do there..

Now, had it gone to Sabre, I think the training problems for the HP agents would be a whole lot worst. Having worked on both, Shares is a much better program to get people trained on. It is more logic based and much easier to understand. Sabre is more powerful, but with power comes complexity so the time needed for training on Sabre is much much much longer than it is for Shares. As a result, HP agents would have a much harder time learning Sabre than the Sabre agents did in learning Shares.