A few weeks ago, we received a request to look at the repeated supported low "blocks" found in Chinto--admittedly, this isn't necessarily present in all versions of Chinto/Gankaku, but since I does show up in the version we practice, and is present in other kata, we figured it could still be helpful. In this example, I use the sinking juji-uke as a choke to provide a simple starting point, since that is a fairly common application for that movement, although there are many others (I actually personally prefer using it as a figure-4 arm lock, which changes the application of the low "blocks" for me). From the choke, I show how the low "blocks" can be used to throw the opponent to the ground, and how it being repeated can simply be showing you to step in front of the opponent and try again, should they step around your initial throw.
What I don't mention in the video is that the kata also gives you another option, should the opponent step around the throw--either the first time, or the second time you try it. This sequence is followed by a hammerfist, then a stepping punch, then a visually-unusual movement that I can best describe by calling it a low supported inverted ridgehand. Since you already have a hold of your opponent, the hammerfist is a simple follow-up to them avoiding the throw. Should they block the hammerfist, it can then be used to pull their block out of the way to clear the path for the punch. The last motion in that sequence can also be used as a "wedge" throw, which enables you to grab the opponent's legs and dump them over yours.