Personally I feel less and less inclined to take TP as a top laner (I would definetly not take it if I could play my pre-rework fiora, but that's another story).
The thing is, if the enemy has a combat summoner and somehow manages to freeze the lane in a good position for them. Often you NEED, REQUIRE AND HAVE TO get help from a team mate (jungler or mid laner usually) to break that freeze and push wave into turret to have lane reset itself, preferably pushing towards you.
But the majority of them got a jessus complex of "I don't have to win your lane for you". TP is a team summoner more often than not (especially in late game). But, due to how many times your team is composed out of assholes, TP will be a detriment in most games as a top laner. So, a combat effective summoner spell (ignite, exaust, even ghost or heal) can win you the lane or help you stay close to your enemy without the NEED of that retarded jungler that instead of spending 20s top to push a wave would rather wait for his own camp to spawn. Coz "win lane yourself, I'm jungling".
That being said, I often can outplay a combat summoner top laner, and have control over the wave. That with a quick back + tp can help me stay ok in lane. But if my enemy is mostly point and click (ie: pantheon, annie) and with a combat spell. Then I'm kind of fucked if they get a good freeze.