The following is a summary of some remedial principles mentioned by Mufti Taqi Usmani. This is in order to avoid the common mistakes in evaluating hadith and making unwarranted objections that one abandons strong evidences.
(1) A hadith is evaluated on the reliability of the sanad and validity of the matn not merely based on the collection it belongs.
(2) The appraisal of the hadith is a tedious task and solely the purview of those who possess the requisite criteria and the rank of ijtihad in the field.
(3) When such experts differ in their appraisal, prioritise the cautious expert over the lenient and the fair over the harsh. If both the experts are fair and cautious one should judge the rationale if they are qualified to do so or else they should choose the one they trust.
(4) Know that the opinion of one expert is not evidence against another expert.
(5) Furthermore, note that the experts judge with the quality of the sources at hand, hence, the loss of information at a later stage does not negate the classification of the earlier experts.
(6) The declaration of sahih or da’if signifies that it fulfils or lacks the set criteria for acceptance; it is highly likely that it reflects the reality but not certainly so. One must act upon the likelihood unless strong evidence indicates to the contrary.
(7) The ahnaf amongst others consider the practice of the sahabah and tabi’in as significant evidence to strengthen a seemingly weak hadith similar to the existence of multiple sanads which in effect reclassifies it to hasan li ghayrihi.
(8) If two reliable ahadith collide, the ahnaf will prioritise the content which conforms to the Quran or the general principles of Shari’ah irrespective if the other sanad is relatively stronger as according to them effect in superior to quantity once reliability is established.
For more details, read Eight Remedial principles in evaluating hadith