Our RO's description of post-tx progress, which I thought was a very useful guide -
once patient could increase from liquids, other than water, (water is actually difficult as it is thin and therefore difficult to control):

If patient could not advance diet to a more challenging food texture each MONTH, RO wanted to be notified. As long as there was some advancement that was considered progress.

It took months for my husband to begin eating solid food and he did have to force himself to step up the diet gradually. Getting the PEG out was a big incentive. Waiting for taste to return is unrealistic as others have said.

An observation as a caregiver - In the beginning, presenting too much of any food overwhelmed him, so I gave him tiny portions. After awhile I noticed that he would never take more, even if he could tolerate the food. So I gradually started adding more food without asking him about it. He would finish but never take any more. Eating can be a very complex process as we've all unfortunately experienced. I'm thrilled to say that he can at least try most foods now and improvement is still occurring.