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Yup. Will tell where contact is or isn't but as mentioned above the stone surfaces should be smooth both sides.

Tried the marker test or looked under magnification at the edge ?

I doubt you have an even bevel or maybe a burr.
http://straightrazorpalace.com/honing/58789-only-sharp-one-side-blade.html

When the razor is sharp is it evenly sharp along the whole edge or is the heel less sharp ???
Any pics of this blade ?
Will it not shave at all after 8k ?

If you've had a good edge & it doesn't hold there can be a number of variables from the steel itself to your honing & stropping skills. The problems related to your own skill, you will eventually...

If you run the DMT a long way off the edge on back & forth strokes it is easy to create convexity. Keep your lapping strokes short & see if that helps.