Mostly he recommended outside English, drawing two rails, when given the option. The other thing he really prefers to get shot angles and that more or less create natural paths to the next position and to keep each position play as simple as possible, even if it means longer shots. He did not really ever suggest the typical power follow inside English shots, but used more direct routes.
Besides the simple position routes, the main point he made about position play was not to stroke any harder than necessary because, as he said "pressure" causes you to miss. Pressure meaning excessive force. Say I was shooting a straight in on a fairly long shot and wanted to draw back a foot to make my next shot shorter on the other end of the table. He said no, just use a stop shot and leave the next shot a foot longer. His logic was you were less likely to miss each ball this way.