Yes and no.James Theesfeld said:Turn timers on certain missions... was a deliberate design choice to prevent overwatch balls crawling around the map. They decided that they didn't want that to define high level gameplay, so they made specific and calculated design decisions to prevent that from happening. If you pay attention to class abilities lots of them are designed around being aggressive or moving quickly to facilitate the turn timer. I've never failed a mission because of the clock. Although one mission I finished on the last turn - but I took extra time to murder guys and I had a run of bad luck that slowed me a turn.
If you enjoy overwatch-balls and super slow methodical map clears that's perfectly fine. I'm not telling you how to enjoy your vidya games. But please remember that they made choices to encourage specific kinds of gameplay. They're features, not bugs.
Having a mechanic in place to push the pace is necessary. They tried with meld and these simple hard timers are a refinement of that. It still needs some work, though. For one thing, too many timed missions is fatiguing for players, and too many of the timers are on the white-knuckle side of what is sensible. More pressingly, at higher difficulty levels the game is extremely unforgiving of tactical blunders, most prominently aggressive up screen movement into fog of war. Your average team of appropriate size and appropriate levels and skills will have the tools to handle one pod at a time without a cascade of wounds and casualties. One. Move your big toe an inch over the invisible line, and you'll be facing 2-3 at a time. In the early game, this could mean 2-3 sectoids running around, and on Legendary they have 10 HP each. You could have 50% or more of your squad mind controlled in a single turn. You could have 3-4 lancers full move-sprinting across the map to incapacitate your entire squad. Encounters rapidly turn from manageable to impossible with the addition of just a few enemies.
The solution to that is intelligent, methodical risk mitigation, which is XCOM is all about. However, the game demanding methodical risk mitigation on one hand and vim, brio and dash on the other because of unforgiving timers puts players in something of a no-win situation. I finished my play through on Commander in spite of this, but I wasn't playing Ironman, and saves can trivialize anything. On my few pokes at Legendary, I can already see half a dozen early missions that would seem unwinnable on their face.
Currently I'm playing Ironman Commander with +2/4 mission turn timers on via a mod, and +1 enemies per pod to balance it out. The extra turns afford me time to have a proper initiation/make use of the stealth mechanic without needing to blind-sprint up the map to beat a clock, the extra enemies makes each encounter 25-33% more challenging. And if I pop two pods, I can have as many as eight enemies running around. It's a good trade off.