When I use the "all" command to display all the lines matching a pattern, it would be useful to have one of two things:
1) An option to be able to specify the number of additional lines of context to expand surrounding the match. (Also have this option on the Selective Display dialog)
2) A command to expand additional lines around a "+" line to view immediate context around a match like "seldisp-expand-context"
I run into this frequently when grokking through log files. I collapse the log file down to the interesting lines, then want to see what went on around that time.