You know my answer, when it comes to preempt style :-)
- Play what partner wants. Results really don't matter unless you can both agree that another style would be better. Better results on this board will be paid back with bad results on future boards when either partner does what they always do and you don't have it this time, or doesn't do what they always do because you didn't have it last time.
- Play what partner expects. Sort of the same thing, but even more so - and especially when it comes to preempts opposite an unpassed hand. Sure, two times out of three the person you disrupt will be an opponents, but nobody will remember those, and your partner definitely will remember the other third, whether it's 3NT-1, or 5♦x-4, or 2♦+3.
- Play what your system is designed for (or redesign your system around what you choose to play). If your partnership is "2/top 3", then why are you playing Ogust (what's the difference between a good suit and a bad suit?) If you play Feature to find 3NT, is partner going to be happy when you have your hand with the ♠K? If you play "feature only with good suit", is partner going to be happy when you bid 3♦ with this and she's looking at ATx?
I play everything from Sound-and-Disciplined (partner thinks, with good reason, that we defend better than the field, so we don't gamble in the auction. She also likes bidding and having me make game when I preempt) to "anything goes" (and this isn't even a dead minimum, except maybe 2nd and unfavourable. Okay, the 7 being the highest spot is ugly) to EHAA (which to the letter of the book, is a pass if the vul is not such that we can open 3
♦. But that was because of the GCC restrictions; with the liberalizing of the Open chart, it's probably a 2 bid) - and anything in between. I will play whatever preempt style partner is comfortable with (but if given the choice, would prefer to be more aggressive than "the field" at MPs or NV IMPs). It's just easier that way.
Now everything David said is valid in theory, and should definitely be used in those partnership discussions. Oh, and find a copy of "Prempts from A to Z" for lots more theory (and a lot of practical ideas). However, bridge isn't played by theoretical players, and "in theory, theory is the same as practise. In practise, that's a good theory." So my arguments are all social.
I do think VUL at IMPs is dangerous; you can go 500 into nothing (or 800 into game) very easily. I like having the kind of internal suit consistency that means I can't have "all the finesses offside". I don't find it happens often, even, though - but when it does, it can throw an entire match. And at teams, you have three "partners" to keep happy. But - making it just that much harder to work out game vs slam, or making a lead-director that sets their game or slam can swing the entire match too.
Now, I also believe in "Rule 1": "if mycroft violates system, or makes an unusual judgement call, and it's wrong, it's his fault no matter what partner did after." If partner is okay with that, and okay with mycroft stepping out occasionally (because I'm right, a lot), and comfortable knowing that they won't be blamed for the disaster later, fine. If not - well, I could change; but those people are likely to want other partners in the first place.
I would also warn against 2
♦ openers; there's a reason there's so many other uses for that call. It's clearly the weakest of preempts. And also most likely to trigger the "is that weak?" ask, for what that's worth. Frankly, there are I'm sure several who would consider this a 3
♦ call, at least NV, because of that.
When I go to sea, don't fear for me, Fear For The Storm -- Birdie and the Swansong (tSCoSI)