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Lobe-dominated radio-loud (LD RL) quasars occupy a restricted domain in the4D Eigenvector 1 (4DE1) parameter space which implies restrictedgeometry/physics/kinematics for this subclass compared to the radio-quiet (RQ)majority of quasars. We discuss how this restricted domain for the LD RL parentpopulation supports the notion for a RQ-RL dichotomy among Type 1 sources. 3C57 is an atypical RL quasar that shows both uncertain radio morphology andfalls in a region of 4DE1 space where RL quasars are rare.  We present new radio flux and optical spectroscopic measures designed toverify its atypical optical/UV spectroscopic behaviour and clarify its radiostructure. The former data confirms that 3C 57 falls off the 4DE1 quasar "mainsequence" with both extreme optical FeII emission (R_{FeII} ~ 1) and a largeCIV 1549 profile blueshift (~ -1500 km/s). These parameter values are typicalof extreme Population A sources which are almost always RQ. New radio measuresshow no evidence for flux change over a 50+ year timescale consistent withcompact steep-spectrum (CSS or young LD) over core-dominated morphology. In the4DE1 context where LD RL are usually low L/L_{Edd} quasars we suggest that 3C57 is an evolved RL quasar (i.e. large Black Hole mass) undergoing a majoraccretion event leading to a rejuvenation reflected by strong FeII emission,perhaps indicating significant heavy metal enrichment, high bolometricluminosity for a low redshift source and resultant unusually high Eddingtonratio giving rise to the atypical CIV 1549.

3C 57 as an Atypical Radio-Loud Quasar: Implications for the Radio-Loud/Radio-Quiet Dichotomy