I have noticed in the USA a lot of certain medicines seem to literally be designed to make the medication difficult to cut in half evenly. With odd shapes and such or the pill is pressed in such a way that it is difficult to do without the pill crumbling. Complete bullshit.
Even have seen them especially with some expensive brand names they say the pills are coated, and shouldn't be cut in half. Only to look at the foreign version of the same pill from the same manufacturer that says it is just fine to cut in half if you do it correctly. I do know some pills you can't cut in half due to certain time release factors, but this wasn't one of them.