Wow. This one is really cool. Don't forget to read the posts at the end. Also check out the vintage photos. This one is dripping with good stuff.
8 Famous Guitar Tones That Were Recorded Straight Into | Reverb News
more helpful mix ideas from Izotope -https://www.izotope.com/en/blog/music-production/9-ways-to-macgyver-your-way-through-audio-production.html
Ear opening explanation and demonstration of this technique - samples included.
Mid-Side (MS) Mic Recording Basics | Universal Audio