There are three schools of thought about the strength needed for two suited overcalls like a Michaels cue bid and unusual no trumps. The first is weak only. This school believes that having two suits will usually allow you to dodge a bad break in one by running to the other. These people will make a two suited bid on Kxxxx in both suits. The second school plays it like a polo mint with a hole in the middle. So they use it as weak (say less than an opening bid) or strong (say 16+) and with the 12-15 range they bid both suits. The problem with this method is that you may never get to show the second suit. I think the best method is to get both suits in quickly and make another bid with extra strength. The minimum strength should be about KQxxx in both suits and KQ10xx in both suits is clear cut. It gives safety as well as a reasonable chance of winning the contract. It is undesirable to bid and not win the contract since the bids only help declarer then.
This hand came from a country congress and we see East opening very light when non-vul in third hand. South does best to make the Michaels cue bid showing hearts and a minor since he knows he will get another bid. When West raises to game, the next bid is a comfortable five diamonds. West doubles since he has two plausible tricks opposite a partner who has opened and then leads his secret weapon, the CA! Declarer ruffs this and plays two top trumps and is pleased that he can now deal with the unlikely 5-0 heart split. When the hearts also behave, declarer can discard two spades from dummy and ruff one for a doubled overtrick and 650 instead of 420. The psyche cost 6 imps because the partner has to double. If West hadn’t doubled, one would summon the director to ask how he knew to make allowance for partner’s psyche. If you want to open in third hand, 2S is safer since partner won’t be expecting any defensive values.