krute tu mAnavA dharma: tretAyAm gautamA: smrutAh !
dvApare SAnkha likhitAh kalau pArASarAh smrutAh !!
It is said that Manu smruti is applicable in Kruta yuga, Gautama smruti in tretA yuga, Sankha and Likhita smrutis in dvApara yuga and ParASara smruti in kali yuga. But ParASara smruti does not deal with the elaborate provisions regarding performance of SrAddha. A smruti is like a policy document . Only in the grhya sUtras, the detailed procedures are explained. We cannot ignore what is said by the sUtrakAras.
The Sraddha prayoga that we practise today is a digested form based on various relevant smrutis and the sutras. Hence we have to take this as the benchmark and try to follow to the extent possible.