What is it then? It is money (capital) coming into the club (introduced) as a result of the Glazers' increased focus on securing more commercial/sponsorship deals.
I think that you think that they should be putting money into United from their own back pocket, am I right? This is what you see as the introduction of capital, yes?
Well, the Glazers don't roll like that I'm afraid. The idea was always to increase the revenues to cover the debts incurred so that the net effect of the debt is decreased or eradicated completely.
Besides, if the only way you can show a profit is by continually putting in money from your own back pocket then you're not really running a business, are you? You're slowly going broke.