The whole point was, if West Ham managed to score , there isn't a credible option to bring on. I don't need to prove that one legged 40 year old Ronaldo is still a better option than anyone currently to have in the box in that situation
Come on. You still don't see how absurd that logic is?
We're on a 1-0 lead. Now you have two options:
1. Go for the kill, keep attacking and score the second goal.
2. Sit back and look for a counter.
We obviously wanted to go option 1. But in the last 15' we lost the midfield battle and were effectively pushed back and had to defend with our lives. Which is actually option 2. Now in this situation you have three options:
2.1 Try to fix the midfield. I think ETH did try but it obviously didn't work.
2.2 Defend and counter to score the second goal. In order to counter you surely need pace and probably fresh legs if possible. Bring Garnacho in for Bruno or Ronaldo for example.
2.3 Do nothing and let opponent score then try to go back into the game. This is the worst option possible.
Once WH manages to score they'd likely to shut up shop and look for a counter. We effectively switch sides. This is the scenario you're talking about.
Again, based on what you're so sure Ronaldo-with-tired-legs could score in like maybe 5' left of the game while he has failed to do that in the previous 85' with fresh legs? You surely need to prove this because this is the sole reason you'd want to keep him on. So far this season he's been shit out or in the box with probably the lowest goal to number of shots ratio and on target rate in the league. Guy can't even hit a barn door now. He's among the worst, if not the worst striker/finisher in the league atm.
Or worse, because they were winning the midfield battle they might try to push even more to score their second goal. The most likely outcome possible after WH scores is simply a 1-1 draw.