There is a mixed opinion and some research being done in this area. Pruning Haskap can be done, but how it is done and what results you will see and how long it will last are questions that have several answers.
Experience has showed that pruning the bottom of the plants after harvesting them will result in a lot of re growth in the same area in the following years (not very effective). Pruning the heavier wood in the centre of the plants results in new branches with more fruit and it's more supple, less likely to break in the next couple of years. Pruning all the edges fairly evenly, results in lots of new growth although not necessarily a lot more fruit in the following year .
Some opinions suggest that pruning the bottom to bring the fruit higher does not work. Pruning the middle opens it up and gives you more fruit (don;t do more than 25%). Pruning all over is too much work and plant ends up too bushy.