notsobigjoe wrote:
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I'm removing my linoleum and laying a piece of Luan over the old piece of Luan with peel and stick tile over that. The old underlayment has become week in spots and I can see where the linoleum is stretching in the low spots....
The floor should not become weak, sag or have any low spots. Putting down an additional layer of luan will not fix the problem. You need to determine the reason for the deterioration and fix it. I would be especially concerned about water intrusion.
Regarding the original question, that gimping is decorative without any structural purpose.