"A stipulation may lawfully include or limit issues or defenses to be tried, whether or not such issues or defenses are pleaded." ( Bemer v. Bemer (1957) 152 Cal. App. 2d 766, 771 [314 P.2d 114]; see Estate of Burson (1975) 51 Cal. App. 3d 300, 307 [124 Cal. Rptr. 105] ["The stipulation furthers the public policies of settling disputes and expediting trials and is by no stretch of the imagination contrary to the policy of California. On the record here, it simply reflected what the parties agreed the pertinent language meant. The stipulation avoided the necessity of expenditure of the time and money of the parties and the public by removing from the litigation an item not in dispute."]; cf. Burrows v. State of California (1968) 260 Cal. App. 2d 29, 33 [66 Cal. Rptr. 868] ["Obviously, plaintiffs did not intend to stipulate away their case while urging it"; there the stipulation would put the party out of court. It is true the Workers' Compensation Appeals Board has the discretion to reject factual stipulations. ( Lab. Code, 5702; see Frankfort General Ins. Co. v. Pillsbury (1916) 173 Cal. 56, 58-59 [159 P. 150] [decided under predecessor statute].) But discretion does not validate capricious decisionmaking ( Bailey v. Taaffe (1866) 29 Cal. 422, 424), and we are unaware of any statute permitting the Board to reject a stipulation clarifying the issues in controversy absent good cause. (See Robinson v. Workers' Comp. Appeals Bd. (1987) 194 Cal. App. 3d 784, 790-791 [239 Cal. Rptr. 841].) It is also true, "The pleadings in a workers' compensation proceeding are deemed amended to conform to the stipulations and statement of issues agreed to by the parties for the record. The pleadings will also be deemed amended to conform to proof if it appears that the parties considered the matter at issue. Pursuant to Labor Code Sec. 5502(d) and W.C.A.B. Rule 10353, stipulations and issues are framed at the mandatory settlement conference (MSC) for later trial at a regular hearing. Discovery closes on the date of the MSC." (2 Herlick, Cal. Workers' Compensation Law (5th ed. 1998) Commencement of Proceedings, 15.36, p. 15-65.0 (Herlick).) But the converse is not true; stipulations are not "deemed amended" to conform to proof, vel non, because the point of a stipulation is to obviate the need for proof. "Labor Code Sec. 5709 provides that no informality of procedure or use of evidence inadmissible under common law or statutory rules of evidence shall invalidate any decision. But, the appellate courts have stressed that since compensation litigation involves adversary proceedings, the basic principles of procedural due process of the law must be meticulously followed, and there must be consistency regarding the record, the findings and the decision." (2 Herlick, supra, Appeals Board Hearing Procedure, 16.1, p. 16-5.)