I disagree with your assessment of the first half, but even if it were true, I think you and some of the other fans are reading to much into a comment.
Telling your wards to stick with the plan, is simply saying ' have faith in your talents and continue to believe. Such statements do not preclude making changes.
For the avoidance of doubt, he did switch positions to start the 2nd half. Sterling went to Left mid and Delph to LCM, before Delph got subbed to push up Dihno and have Nando cover Okazaki.
There were contingency plans for 'almost every scenario. You could see it in everything we did, I can outline some of them.
Dihno on Okazaki: man for most of the game. Literally followed Okazaki on every dead ball. Purpose was to have the 2 CBs double Vardy.
Over/Under on Vardy: Both CBs played over under on Vardy all game. If Vardy was on the left Demi was over and Ota under, if he went right they switched, Ota closes and fronts and Demi drops.
Demi didn't go up for a single cornerkickthat ciz they had to keep 2 on Vardy. Him and Zaba. Zab played over when Ota went up for Corners and Demi played under. His only over the top break on goal was an error by Demi, who was attempting to switch the over under with Ota as Vardy was going towards the left, then cut middle.
Delph played help on Mahrez on the left. Mahrez finished with a 47% pass completion. Worst of the season. His goal was an error on Delph, who was ball watching as Mahrez ran past him. Before receiving the ball.
3 second retrieval. When we lost the ball, first defender (I.E closest player to the ball is supposed to attack it immediately and try to retrieve). If we can't regain it in the first attack, the defenders retreated to the top of our 18 box . This happened all night we retrieved a high percentage of our ball in their half. Zab, Ota, Delph, Sterling, Aguero all accomplished this at different times.
Our real problem in the game was our play around their box. Enough players simply weren't crashing the box. Everyone was checking out to the top of the box for the ball. Silva, Aguero, Sterling, all kept coming out of the 18 for the ball.
Coach instructed Yaya to play higher when we had the ball, Yaya moved up or tried crashing the box. Got 2 shots off but he wasn't as effective. Him and Silva pretty much were doing the same thing. Trying to set up others.
Pellars then switched Delph and Sterling, coz Delph is actually a good box crasher. Sterling went left. Then they scored the 2nd.
He pulled Yaya and Delph, to get Dihno higer up the field, and a natural box crasher in Ian on the field.
We lost that game, but the tactics and maneuvers by our coach was quite considerable and easily identifiable.
But then again, when folks don't like you, they don't like you. Nothing you do can change that.