"could rise to over the allowed amount for your site". (quoted from the above Answer).
Whilst I agree with the conclusions, this statements needs clarifying.
Part of the process of planning demands satisfaction of the access arrangements at the point of emerging onto the highway. The std of access required depends on the type of highway, the average speed of vehicles on that highway and the number of dwellings needing access. In the case of developer seeking permission for a whole new residential site, he might need to propose a new mini-roundabout, for example, before the site access is acceptable.
It is therefore very logical that what you have proposed and was accepted for one dwelling is not the same as what is required under a different application.
If that is the entire basis under which you have presented your case at Planning Appeal, I fear you will not succeed.