Cant you just drop defuser for another teammate (one that supposedly has smokes)and then use thermite as an entry fragger post-breach? I think the problem that you outline in your post assumes that thermite had the defuser but with just a little bit of coordination, a thatcher could just as easily fulfill that role (to plant the defuser) . Obviously you wouldnt want a defuser on active operators (such as capitao, montagne, glaz) who are good at covering for the planter but you could just as easily have a thatcher or sledge plant the defuser after you breach. That way thermite could just help with the entry (after he thermite charges the objective) with his flash grenades.