The concept of blockade was aptly demonstrated by Nimzovich when he advised, "First restrain, then blockade, finally destroy!" In fact, he even wrote a book on blockading, Die Blockade. This little appreciated book was translated in to English over thirty years ago and a new translation was published a few years ago. Even today it contains a lot of good instruction.
I have always been intrigued by the following game in which Gligoric had two passed Ps on the Q-side and what looked like an excellent position, but Szabo showed how to render them impotent.
The game, played at Helsinki Chess Olympics 1952 (OlympBase has a full article on this event HERE), is a good example of blockading by BOTH sides. Pachman presented this game as an example of blockade strategy and his light notes illustrated the points very well, but as is often the case, it wasn't the one sided positional shellacking that a casual examination would indicate. Engine analysis with Stockfish and Komodo turned up resources for both sides, but Pachman's general evaluation is correct. The line chosen by Gligoric left him struggling by move 13 and a couple of other games from the same position did not turn out well for white either. As one might expect, it was a great game between these two titans and Szabo's play was very instructive.