Accretive / Dilutive Question

Hi,

I'm trying to get my head around merger consequences analysis and whether a deal is accretive / dilutive when funded through debt.

I understand that the deal will always be accretive if:

Net income of target + tax effected synergies > tax effected D&A step up + tax effected cost of debt

However, I've read on the forum that if the cost of debt is higher than the equity yield ( inverse of the P/E ratio), then the deal will be dilutive. I can't really get my head around this, I understand it logically, but I don't see how it is true in practice.

The cost of debt is going to be a small percentage of the purchase price - this is not linked to the actual earnings of the target. As long as the additional earnings from the acquisition are higher than the interest expense, surely the deal will always be Accretive regardless? Would the cost of debt not have to be huge to outweigh the additional earnings achieved?

Basically, i'm not sure I understand how the target's share price and earnings are linked to the acquirer's cost of debt.

Thanks for any help.