Comparing multiple dates in date table

Here is a sample of the data in the subscription table - each Dateid links to the date dimension dateid with the signup date being the active relationship

I think my question is more of an idealistic one. I was under the impression that the best designs kept the date values in the date dimensions, linked by the a key rather that actual dates, and ideally one but splitting out into additional date tables (i.e have 1 date table fot the signup date relationship, 1 for paiddate and 1 for end date) is an acceptable choice.

However to use the equation I have I could only get it to work if I put the actual date in the main table which kind of defeats the object.

How can I change the relationships so I can access the date values in the date table more than once in the equation

so this code

 'subscriptions'[Paiddate] <=max('Date'[Current_month_end_Date])
             && ('subscriptions'[ENDDATE] > max('Date'[Current_month_end_date]

becomes (something like:

'date'[date]<=max('Date'[Current_month_end_Date])           -- Using Paiddate relationship
 && ('date'[date]> max('Date'[Current_month_end_Date])      -- using enddate relationship

or could you use a lookup of somekind to use the PaidDateID to return the date value into this measure 

Lookup('subscription'[Paiddateid],'Date'[Dateid],[date] <=max('Date'[Current_month_end_Date])

Is this possible - As my equation works I am really looking for the most effiecient way of using the date table and avoid replication of information in tables {having the ID and the actual date in the main tables is a bit pointless)

Cheers - hope this makes sense!!