Endurance vs technique

Hard sets with short rest intervals have the same issue, after a while your technique starts to decrease, and your tired body is not responding so well. I wonder if is worth it to scarify technique for endurance or endurance for technique. The obvious answer: “well, it depends on where you are and your goals”. Please don’t I think crazy hard endurance with bad technique occasionally is a very good thing, but if you always do it that way you will eventually get use to bad technique, but if you concentrate too much on technique while you suppose to go very fast, you won’t get that extra for muscle. For example, let’s say this set must be done with very short rest 12 x 25 fly 2 x 200 IM 3 x 100 *** 2 x 200 IM 4 x 75 back 2 x200 IM My point, Is really hard to keep good technique on those second 200 IMs, but if I’m looking for endurance you have to go fast... What do you think about adding easy swims? 12 x 25 fly 100 EZ 2 x 200 IM 100 EZ 3 x 100 *** 100 EZ 2 x 200 IM 100 EZ 4 x 75 back 100 EZ 2 x200 IM It would be much faster (speed), better technique, but…not so “hard” (I’m thinking of endurance), like adding more rest. You can work on technique or endurance any time, but the key thing while racing is to maintain good technique at high speed during a long period. How do you deal with endurance vs technique?