Irma just grazed the flat part of Cuba, no mountain. The Windy.com website showing Irma in the middle of Cuba was flat out wrong. Radar and satellite both showed the center brushing the coast.
The land interaction definitely helped weaken Irma, but that was due to the length of interaction. Irma slowed down passing the island.
That long coastal Cuba route slowed it, weakened it and caused the eye to wobble like crazy went it left Cuba. That coastal travel scenario can lead to a double concentric eye morphing into oscillating eyes vortices. From what I have read.
If the eye was on the coast, the circulation was impacting the mountains ( and vice versa)
Whatever... the point is: the worst of the forecast called for a turn before Irma had much interaction with Cuba. Thankfully, she did.