A distinction is often made between Tradition and tradition, and I have seen this distinction used in arguments attacking the position of traditionalists. Essentially the point is this: that Tradition (big "T") is irreformable, while tradition (small "t") is changeable. Traditionalists are criticized for rejecting the fact that the smaller traditions can change. Hence their stubborn refusal to accept such things as the New Mass and other innovations.
As a traditionalist myself, I actually have no problem with this distinction in itself, for there really and truly is a difference here. Big "T" tradition, also called Divine Tradition, is that Tradition which constitutes a remote rule of faith for Catholics, next to and equal to the authority of the scriptures themselves. This Tradition is intrinsic to the Deposit of Faith. But small "t" traditions, on the other hand, are those traditions which are not intrinsic to the Deposit of Faith, for example, liturgy and discipline. Hence they are called "extrinsic" or "ecclesiastical" traditions. Fr. Chad Ripperger makes this distinction in his article Operative Points of View, which I highly recommend.
However, as can be deduced from Fr. Ripperger's explanation, the Divine and ecclesiastical traditions are not strictly speaking separable from each other. In fact, the smaller traditions are inherently directed to the purpose of preserving the Deposit of Faith itself in the minds of the faithful. Thus, there is in fact a very intimate connection between the two kinds of tradition. The smaller traditions develop always as a means of expressing the larger Tradition, and are always built upon it as on a foundation.
From this it can be drawn that, while the extrinsic tradition is inherently more changeable than the intrinsic Tradition, nevertheless the extent and manner in which it may be changed is governed strictly by certain principles deriving from its intimate connection with the Divine Tradition. Thus, while it is a legitimate distinction, the distinction is not so stark that the two kinds of tradition are independent of one another.
One of the distinctive marks of the traditionalist movement is its insistence that the smaller traditions of the Church be restored, and that we return to the organic process of development by which they have formed over the centuries. This means there must be a return to the principles by which this tradition must develop. These principles consist in the extrinsic tradition's close connection to the intrinsic Tradition, that it is a means of preserving it and keeping it alive in the thought and practices of the faithful. In application, this means that a radical change or abandonment of the smaller traditions will probably result in an abandonment of the greater Tradition itself, in the minds of the faithful. And indeed, this is exactly what has happened in the Church today. Whether mainstream Catholics are aware of it or not, they are no longer living in the extrinsic traditions of the Church. As a consequence, there has been a massive loss of faith itself.
This is why it is possible to say that tradition in general - whether it is the Divine Tradition or the ecclesiastical tradition - is what constitutes a rule or standard of orthodoxy for Catholics. Obviously if one adheres to the Divine Tradition one's faith will not fail. But there is a logical connection between the Divine Tradition and the extrinsic tradition such that chances are one's faith will be much better safeguarded by embracing the smaller tradition as well. And indeed, this is the very purpose for which the Church has ever had the smaller traditions.
An application of this principle is the oft-quoted-by-traditionalists maxim, lex orandi lex credendi: the rule of prayer is the rule of belief. Specifically, this is an application to the liturgy, which is one of the prime examples of a small "t" tradition which is intimately connected to the Divine Tradition. While the liturgy as such is not part of the Divine Tradition, it is nonetheless the Church's prime expression of the Faith in the worship of God. It is only logical, then, that in practice the strength of faith of the people has corresponded with the worthiness of their prayer; and this is true with regard to liturgical prayer as well. The traditions of liturgical prayer corresponded with the Tradition they expressed. And as is observable in today's Church, the degree to which the faithful have embraced the traditions of the liturgy has corresponded with their embrace of the Tradition itself. Today, both traditions have quite deteriorated in the minds and lives of the faithful, and unsurprisingly so.