SXT[CLC]s[/CLC] and TOAD[CLC]s[/CLC]: Close Encounters of the Same Kind

We show that, apart from having in common long intervals between large-amplitude outbursts (without intervening normal outbursts), soft X-ray transients (SXTs) and "tremendous outburst amplitude dwarf novae" (TOADs) have very similar optical light curves, showing glitches and superhumps during the main part of the outbursts, and considerable postoutburst activity in the form of one or more minioutbursts. We propose that these similarities reflect that both SXTs and TOADs have very small mass ratios and very low mass transfer rates. The outbursts of SXTs and TOADs are triggered by a viscous instability and are almost always followed by a tidal instability during which superhumps develop. We suggest that the increased mass accretion during the glitches is caused by enhanced tidal dissipation.