Dont think it means that, more a case of if he is talented and fees involved, why play him out of position. I would sell him if we were buying replacements, but if its just a choice, I would rather sell Lukaku and at least let him battle it out with Rashford and sign a proper left winger with the Lukaku money.
Many young talent, wonder boys ended up with so so career. Football is not just about early bird. Someone like Luis Suarez who reached top level later achieved a level above many wasted former young talents. For example, Luis Suarez at his best is better than Anelka had ever displayed who was at one time second most expensive player,in the world just behind then already best player award Ronaldo. Anelka however couldn't be denied that in raw talent term is on same par with the best forwards of his generation.
Dembele, Coutinho cost like double to triple Martial fee and can still be on the bench. Barcelona bought Malcom when they don't really need him for similar fee to what we paid for Martial. Fee means nothing. If it doesn't work, then it doesn't work.
The no 9 position is there to be taken. Martial had been tried, and passed by not just one managers . I'd already touched on Martial first season for us. Remember how in the end, LVG kept Rashford as no.9 with Martial as left side forward. So even LVG ain't 100% following through with Martial is dead on central forward line of thinking. This whole thing is more wishful thinking than anything.
Edit:
Was Young really being targeted like one of the poster said? If Martial had to defend for Young and relative position show it's mostly against Sergio Roberto, then how come Martial covered so little ground when his mark supposed to be a full back pushing up the pitch?