Happy to be helpful. I don't remember when I first learned about '~' in vi, but I've used it an awful lot since then. Then again, when I started feeling comfortable in vi, it felt like I only understood about 1/20 to 1/10 of what it could do but that small portion was enough to make it a pretty powerful tool; since then I've learned a lot more of it, but I've also switched to using vim on my home machines ('cause that's what comes up when you tell Linux to run vi), and I know vim has a bunch of new features that I haven't gotten around to exploring (along with a couple that I've gotten used to and have to remind myself vanilla vi doesn't have when I'm on a SunOS machine).
The only problem with vi (well, for me anyhow -- the modal aspect really bothers some other folks) is the temptation to do large search-and-replace operations with a wickedly long command with complex regular expressions in it that is (because it's so long) too likely to wind up with a typo in it. If I could have command-history -- tell it to show me the last command I tried and let me fix the typo or thinko in it -- then that wouldn't be such a problem. (But when the long commands work, there's a certain smugness that results from completely restructuring a file with a single command.)
(no subject)
The only problem with vi (well, for me anyhow -- the modal aspect really bothers some other folks) is the temptation to do large search-and-replace operations with a wickedly long command with complex regular expressions in it that is (because it's so long) too likely to wind up with a typo in it. If I could have command-history -- tell it to show me the last command I tried and let me fix the typo or thinko in it -- then that wouldn't be such a problem. (But when the long commands work, there's a certain smugness that results from completely restructuring a file with a single command.)