Drawcall increase when do highlight on a gameobjct which imported from maya, plz help me

I'm working on highlight a gameobject in unity, what i'm doing is make gameobject able to change color(change to white and change back), may be same as fadeout/fadein. I'm instuck with this, i able to make it work if gameobject is standard unity object(ex: cube), drawcalls will be 1 b4 do highlight, will be 2-3 while highlight is working, and after highlight finish, drawcalls go back to 1.

However when i do highlight on a gameobject which 's imported from autodesk maya 2012, after do highlight, it keep drawcall is 2-3 after highlight finish, i don't know why, because 2 cases 're using the same material, and the same texture, and only have 1 code to do highlight, I attacked unity project below, can anybody help me figure out what 's problem?

Note: i have 2 scene, Test1 is a case that drawcalls inscrease after do highlight, and Test2 is not, when play, plz hit button number 1, 2 to do highlight

Sorry for my english, thanks a lots

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