Easy, tuc has dealt with your attempted denunciation of DV's points far better than I could. So I merely add, "wot he said!".
how would MOD's reputation suffer
believe me, that is not a problem.
we, alone among F35 partner nations, had compromised the stealth characteristics of the aircraft by cutting holes for after-market TCAS?
Then don't cut holes, find another solution. Let the ingenuity be expended there instead of in endless years of not doing anything.