Issues with posting description

Our Sales Invoices are mainly using Resource or G/L Account type rather than Item and has been heavily customized. This is because we have 3 Finance Departments with difference businesses and requirements sharing a common database and reports.

In our situation, if our invoice has 10 G/L Account items of the same G/L code, they will be posted into G/L as 10 separate entries using the line description but posted into Customer Ledger as 1 merged entry using the posting description. To me, this is inconsistency. Both G/L and Customer Ledger Table should be having the same entries, isn't it?

However, if our invoice has 10 Resource items of the same Resource code, they will be posted into G/L as 1 merged entry using posting description append with billing period, same as Customer Ledger Table behaviour.

The problem with using posting description that used the first line description append with period is that if the first line item is water bill and second line description is electricity bill, the G/L Code under electricity bill will also receive water bill description append with the billing period. Unless we switch to use line description and not merge the line items, which will make G/L ledger extremely lengthy.

I would like to know the default NAV behaviour and the common practice in your companies regarding how Sales Invoices with multiple sales line items get posted into the General Ledger and Customer Ledger.