No it won't. I don't know what 8-ways you have, but my 8-ways have no square restrictor in them at all making any 4-way game (rotated 45 degrees or not) impossible to play "properly".
We're talking about the T-stick+, as stated numerous times. The T-stick+ DOES have a square restrictor. If you're using an 8-way with a round restrictor, then this trick will not work for you, and 4-way games will play badly, just like you say.
I cannot for the life of me understand how hitting the diagonals on an 8way is any better than hitting the straights on ANY game designed to use a 4-way (square restricted) controller...
It doesn't matter to the game whether you're hitting diagonals or not. If you configure MAME to watch for diagonals coming from your controls, then send 4-way signals to the emulation, then your game will play exactly as if you were using a 4-way, even though you're not. That takes care of the electrical portion.
But the feel is the important issue. If you're using a rotated 4-way, you've got a square restrictor. If you're using a T-stick+, you've got a SQUARE RESTRICTOR! When you push the stick into the corner of the square, it feels the same to your hand whether you hit one switch or two.
If it PLAYS the same, and it FEELS the same...
AND it isn't just up-right it could be right-up and if you don't hit them in the right sequence you are hosed, q-bert will not move.
When you push a square restricted stick into the corner, you don't hit up and right in sequence, you hit them at the same time! It's not up, THEN right.. It's up AND right at the same time. So Q-bert will move just fine.
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I should point out, I've stated on this board repeatedly that I've always preferred Wico leafs. I'm not saying that this is the best method out there, and everybody that doesn't like it is wrong. In point of fact, I'm planning a fully modular setup, and probably will have a rotated 4-way module for it. Depending on your choice of sticks, this solution may not work worth a hoot for you.
This solution is especially intended for people using the T-Stick+, who want to avoid the Frankenpanel look. Especially if they intend to have only one control panel. But every time the rotated 4-way discussion comes up, I keep seeing NoOne=NBA post this solution, and I keep seeing folks just not get it. I'm just trying to help get the message across, for the benefit of the noobs reading this and trying to decide which sticks to buy, and how to lay out their panel. This is an OPTION, folks!