That's exactly how it happens. Your plants begin to stretch and boom, you begin to see the yellow zebra stripes.
Here's why ... LED lights seem to require the use of much more Mg and frequently Ca than HID and other forms of lighting. It's important to realize that Mg is the center most atom in the chlorophyll molecule so essentially that means its the foundation on which the chlorophyll molecule is built. If there's not enough Mg available, you see that tiger striping and eventually that leaf tissue dies. This is a light based reaction so dimming of the lights as well as supporting your plants with extra Mg is critical to its recovery.
It's also important to keep in mind that those leaves that show the tiger striping may never recover. Look at new growth to determine your progress. Mg also absorbs best (in soil based media) with a media pH of approximately 6.5 +/- .2
Edit: Above is the short answer ... a still short but more detailed answer can be found here:
en.wikipedia.org
especially being LED. Did you do the foliar?? lol .. it really is the difference between them recovering in ~2 days, or 1 week. Don't be scared of the so called "water droplet magnification" thing..it's largely been debunked.. especially since you can lower and dim your light...foliar feed it atleast twice per day,. during lights on, generally the stomata close at night.
